Science & Law Blog

Perils of Bite Mark Evidence

The New York Times today tells the story of  Roy Brown, who was convicted for the 1991 murder of Sabina Kulakowski.  A recent DNA test of the purported real killer's daughter appears to exonerate Mr. Brown of the crime.  The daughter was needed to supply DNA because her father committed suicide just days after Mr. Brown wrote him a letter accusing him of the crime.  A major piece of evidence used to convict Mr. Brown was forensic bite mark evidence, a particularly suspect form of forensic "science."  The bite mark testimony was offered by Dr. Edward Mofson, and concerned the identity of six upper teeth-marks, despite the fact that the defendant only had four upper teeth.  Interestingly, the defense offered the expert opinion of Dr. Homer Campbell, who vehemently disputed the prosecution's expert's identification.  The jury believed the prosecution's expert.  This case thus illustrates not only the bankruptcy of bite mark forensic evidence, but also the added value of having some sort of effective gatekeeping standard to exclude this sort of bogus testimony in the first place.  See full story here.
--- DLF

Women in Science -- The Trenches

Women continue to occupy a disproportionately small percentage of working scientists.  This fact is a product of a host of forces, but appears to be changing -- if ever so slowly.  The New York Times today has an excellent article on the cultural changes now taking place, and on those that remain in need of considerable attention.  See full article here.
--- DLF

European Parliament to Regulate Toxic Substances

A law passed by the European Parliament today will require manufacturers to register "30,000 chemicals used in everyday products," in effect beginning a comprehensive scheme of regulation.  (See NY Times article.)  Predictably, the law has critics on both sides, with industry concerned about costs and the effect of bureaucratic red tape on innovation, and environmentalists complaining that it does not go far enough.  In any event, it seems to be an important step toward addressing the disturbingly little toxicological data we have on the many chemicals used in commerce today.  The tort system seems woefully unsuitable for improving our knowledge, given its high administrative costs, its limited time horizon, and its deterrence of research by manufacturers (since bad results create liability).  A comprehensive testing scheme seems like a far more sensible solution.
-- EKC

San Francisco Bans Toys with Plastic Contaminants

CNN/Time Magazine, in a recent article entitled “What's Toxic in Toyland,” reports that San Francisco has banned certain plastic toys for children under 3 because of a fear of plastic contaminants. The contaminants are suspected of mimicking or interfering with hormones, leading to a variety of endocrine and reproductive problems. (See also the original story from the San Francisco Chronicle.) The Daubert-versed reader will notice a familiar refrain in the controversy surrounding the ban. Consumer and environmental groups accuse industry of ignoring a potentially significant public health problem. Industry groups and other critics in contrast argue that the proponents are unduly alarmist, and emphasize that the only current evidence of toxicity consists of high dose studies in rats.

One significant difference between the toy and Daubert contexts, however, is that one involves an ex ante regulation and the other an ex post liability determination. Liability determinations require proof of causation, suggesting that some preference for more definitive epidemiological studies may be appropriate. (Some academics, including my colleague Margaret Berger, have questioned the wisdom of demanding proof of causation, but it alas remains the law.) Ex ante regulation, to the contrary, can operate on a more precautionary principle.  San Francisco, for example, has essentially reversed the burden of proof, requiring the toy manufacturers show the plastic contaminants are safe before selling the toys. There is precedent for this – consider new pharmaceuticals and the FDA.

The end of the CNN/Time article alludes to imminent litigation by toy manufacturers to “block the law.” One imagines that their theory would be preemption due to various EPA regulations in the area. Most recent preemption controversies, however, have again been focused on the preemptive effect of a federal regulation on ex post products liability. The San Francisco ban potentially complicates the analysis by pitting a stricter local regulation against a laxer federal one.

--EKC

Global Warming Study Group?

Although it is unlikely that President Bush will follow the Iraq study group's recommendations to the letter, the fact that this group existed at all -- and brought its collective wisdom to bear on the intractable problem of Iraq --  speaks volumes.  Perhaps we will finally stop "staying the course" in one context in which such a direction was leading so clearly into a brick wall.  Another area crying out for independent assessment and recommendations is American environmental policy.  It is not clear that this President has any intention other than to stay the course in the battle against global warming, which poses potentially even greater dangers to the planet than this president's myopia on Iraq.  The president should assemble, possibly with the assistance of the National Academies of Science, a high-level study group to analyze the current situation and make recommendations for public policy.  The President might even consider making Al Gore co-chair of this group.  Time is of the essence and something needs to be done.  A presidential study group might just give our policy makers sufficient cover to allow this Nation to once again be an international leader on a subject that concerns the entire world.
--- DLF

The Supreme Court and Science

Nice article here about the intersection of law and science, and particularly at the Supreme Court.  See Here.

Judicature and Scientific Evidence

The most recent volume of Judicature has an interesting series of articles on a range of science and law related topics, including one by our own Ed Cheng.  The full volume can be found HERE. 

The list of articles follows:

Should Judges do independent research on scientific issues 
by Edward K. Cheng, an associate professor at Brooklyn Law School (edward.cheng@brooklaw.edu).

Appellate courts must conduct independent research of Daubert issues to discover "junk science" 
by Michael E. Keasler, a judge on the Texas Court of Criminal Appeals (michael.keasler@cca.courts.state.tx.us) and Cathy Kramer, a staff attorney at the Texas Court of Criminal Appeals..

Appellate courts should resist the temptation to conduct their own independent research on scientific issues, by Sharon Keller, Presiding Judge, Texas Court of Criminal Appeals (Sharon.Keller@cca.courts.state.tx.us) and Donald Cimics, a research attorney at the Texas Court of Criminal Appeals.

Independent research on scientific issues by judges must be carefully weighed and considered
by George Marlow, an associate justice, New York Supreme Court, Appellate Division, and co-chair of the New York State Advisory Committee on Judicial Ethics (gmarlow@courts.state.ny.us).

Virginia's answer to Daubert's question behind the question 
by D. Arthur Kelsey, a judge on the Court of Appeals of Virginia, and formerly a judge of the Fifth Judicial Circuit of Virginia.

Questioning judges about their decisions: Supreme Court nominees before the Senate Judiciary Committee, by Margaret Williams, an assistant professor in the Department of Political Science at Goucher College (margaret.williams@goucher.edu) and Lawrence Baum, a professor in the Department of Political Science at The Ohio State University (baum.4@osu.edu).

Meeting the challenge of educating court managers
by Roger E. Hartley, an assistant professor of public administration and policy, and assistant professor of law (adjunct), and c0-director, Law, Criminal Justice, and Security Program, at the University of Arizona (rhartley@arizona.edu) and Kevin Bates, fiscal analyst for the Joint Legislative Budget Committee, Arizona State Legislature.

How we can improve the reliability of fingerprint identification 
by Michael Cherry, president of Cherry Biometrics, which designs identification systems. He is Vice Chair, Digital Technology Committee, National Association of Criminal Defense Lawyers (NACDL) (mcherry@cherrybiometrics.com) and Edward Imwinkelried, the Edward L. Barrett, Jr. Professor at the University of California, Davis, School of Law (ejimwinkelried@law.ucdavis.edu).

Science and/or Religion

Don't miss this article about the relationship between science and religion or, perhaps more aptly stated, their current separation and pending divorce.  See Article Here.
---DLF

Scientific Methods

It has been a recurring debate among the cognescenti who study science and law as to whether there is any such thing as "the" scientific method.  Among working scientists, of course, there is really no debate, since that is what they do for a living.  It may very well be that there is no one METHOD associated with SCIENCE.  But there are certainly METHODS that are, and that is what scientists do when they test hypotheses.  Hypothesis testing, albeit using a very wide variety of paradigms, is what constitutes the scientific method (or scientific methods, if you prefer).

Well, today's blog is not the place for me to engage this debate fully, if a blog is ever quite appropriate for such matters.  But a story in today's New York Times made me think of this debate, since it chronicles what it calls "the best science show on television."  The show, on the Discovery Channel, is called "Mythbusters."  The hosts like to "blow things up," and in so doing teach us all a lot about science.  The show, as the story tells it, is not really a science show at all, since they don't teach "science."  They do, however, teach the core lesson of science, which is to test hypotheses.  It's an important lesson, and one that all lawyers, judges, and policymakers could benefit from learning.  Now if we could just get the show to devote a few episodes to some of the forensic identification sciences, or clinical medicine, or clinical psychology/psychiatry.  Unfortunately for all of us, these subjects, possibly with the exception of arson investigation, do not lend themselves to fires and explosions, and thus do not make good television.  See Story Here.

No automatic DNA collection before conviction

In the first opinion of its kind, the Minnesota Court of Appeals recently struck down a law authorizing the taking of DNA samples from those who have been charged but not convicted of crimes.  In In re Welfare of C.T.L., 722 N.W.2d 484 (Minn. Ct. App. 2006), a juvenile was charged with assault and aiding and abetting a robbery. The state moved for an order requiring him to provide a biological specimen for DNA testing as required by an amendment to Minnesota's offender DNA database law, Minn.Stat. § 299C.105 (Supp.2005).

The Court Appeals agreed with the defendant that automatic DNA sampling before any conviction is obtained violates the Fourth Amendment.  The court distinguished the many cases upholding the constitutionality of compelling convicted offenders to contribute samples to a databank for identification as follows: "an individual who has been convicted of an offense has a reduced expectation of privacy and . . . the reduced expectation of privacy . . . is not present here."

At least six other states and the federal government require DNA sampling before conviction. If a court upholds such a law, I predict that the Supreme Court will weigh in. Before this opinion (which is none too deep), the issue was debated by a few law professors. See, e.g., Who Needs Special Needs? On the Constitutionality of Collecting DNA and Other Biometric Data from Arrestee, 34 J. L., Med. & Ethics, 188 (2006); The Constitutionality of DNA Sampling on Arrest, 10 Cornell J. L. & Public Policy 455 (2001).

Conference at John Jay College

John Jay College will be hosting a conference to mark the 100th anniversary of Hugo Munsterberg's "On the Witness Stand" on March 1-3, 2007.  The Conference is entitled "Off the Witness Stand: Using Psychology in the Practice of Justice."  According to the announcement,

“Off the Witness Stand” will bring scientists and justice system practitioners and policy-makers together to see where we stand now in answering Munsterberg’s call to inform practice with science (and science with practice), how we got here and where we are going. The conference will include presentations by psychologists, by practitioners from many points of the criminal justice compass, and by leaders in justice system reform on topics including : perception, witness memory and testimony, deception detection, confessions, forensic assessment, competency and treatment in forensic settings, expert testimony, jury decision making, courtroom procedures, crime prevention, and the influence of psychological research on the legal system.

Plenary and other invited speakers include former United States Attorney General Janet Reno, Thomas Grisso, Saul Kassin, Amy Klobuchar, Elizabeth Loftus, John Monahan, Steve Penrod, Barry Scheck, and Gary Wells.

Looks to be an interesting event.  Information can be found Here.  And for those interested, the call for papers can be found Here.
--- DLF

Cholera, Epidemiology & John Snow

Steven Shapin has an excellent essay and review of Steven Johnson's new book on John Snow and his founding of the discipline of epidemiology.  Johnson's book is "The Ghost Map: The Story of London's Most Terrifying Epidemic -- and How It Changed Science, Cities, and the Modern World."  Shapin's compelling review can be found HERE.
--- DLF

Statistics and Supreme Court Clerks

David Kaye and Joe Gastwirth consider whether the drop in the number of women law clerks at the Supreme Court is statistically significant.  Their answer?  Not based on the data available!  See Here.

Endangered Species

The Washington Post reports that "A senior Bush political appointee at the Interior Department has rejected staff scientists' recommendations to protect imperiled animals and plants under the Endangered Species Act at least six times in the past three years."  See Article Here.  According to government documents, the appointee, Julie MacDonald, a deputy assistant secretary of the interior for fish and wildlife, "has repeatedly refused to go along with staff reports concluding that species such as the white-tailed prairie dog and the Gunnison sage grouse are at risk of extinction. Career officials and scientists urged the department to identify the species as either threatened or endangered."  The article continues:

Hundreds of pages of records, obtained by environmental groups through the Freedom of Information Act, chronicle the long-running battle between MacDonald and Fish and Wildlife Service employees over decisions whether to safeguard plants and animals from oil and gas drilling, power lines, and real estate development, spiced by her mocking comments on their work and their frequently expressed resentment.

It appears that this situation is just one more in an agonizingly long list of instances in which the Bush administration ignores or distorts science in an effort to cater to its industry supporters.
--- DLF

The Toxic Effects of the Dust at Ground Zero

The NY Times has an interesting article this morning on diseases suspected to be linked to the dust created  by the collapse of the World Trade Center towers.  See http://www.nytimes.com/2006/10/24/nyregion/24toxic.html  The problem, of course, is the familiar and knotty one of causation.   On one side are those who would like to set high standards of biological plausibility and nearly unequivocal proof; on the other are those who complain that such standards are nearly impossible to meet and are excessive for establishing causation for legal purposes.  For example, in the case featured in the NY Times article, the victim was awarded compensation from the 9/11 fund, but the medical examiner refused to place the victim's name on the list of 9/11 victims, citing the lack of sufficient medical proof.  As is often the case epidemiological studies have been slow to materialize, perhaps complicated by potential latency periods and the relatively small sample size.
--EKC

Handwriting Identification in the News

According to the New York Times today, a handwriting expert, Gus Lesnevich, who was hired by  Brooke Astor's court appointed lawyer, has concluded that Mrs. Astor's signature on a change to her will is a forgery.  Lesnevich, according to the story, said that

Mrs. Astor “could not have written the questioned ‘Brooke Russell Astor’ signature dated March 3, 2004, due to the deterioration of her ability to write her name.”

Mr. Lesnevich reviewed examples of Mrs. Astor’s signature going as far back as 1992. In his report, he asserts that “in this case, the questioned ‘Brooke Russell Astor’ signature and known signatures of Brooke Russell Astor contain elements of dissimilar letter formations” and dissimilar “execution.” He said the 2004 signature was different from signatures executed less than a month earlier and about six weeks before that.

As we document in our treatise, Modern Scientific Evidence, the empirical validity of the field of handwriting identification is questionable, at best.  The Times' story does not give any more detail regarding the expert's conclusion (See full story here. ), but what is provided is a rather thin reed on which to hang such a momentous opinion.  His conclusion appears to be based on a combination of biomedical physiological assessment and variability of handwriting in the elderly, premises that almost certainly have either no empirical basis, or which this expert has no expertise.  The signature may indeed be a forgery (or not), but no one should think that the expert's opinion on this matter is founded on sound scientific authority.
--- DLF

Drowsy Memory

Although perhaps not on-point to the subject of this blog, a story in Science today regarding sleep deprivation and memory is quite interesting nonetheless.  Neuroscientist Matthew Walker, from Harvard, found that students who had gone without sleep the night before did considerably (and significantly) worse in a word-memory task than students who had a normal night's sleep.  The sleep-deprived students recalled about 40% fewer words.  The researchers found, however, that words with strong negative connotations were remembered better (e.g., cancer or jail) than those with positive associations (e.g., sunshine or happy).  The researchers suggested that the brain might remember negative words better under such circumstances, because such skills were adaptive in evolutionary terms.  In a follow-up study, fMRI skans indicated that sleep-deprived students had less activity in the hippocampus.  The story explains that "[t]his suggests that just as sleep is important for consolidating new memories after they're learned, as other studies have shown, it's equally important for preparing the brain to learn new things the following day."  The full story can be found here.
--- DLF

Science in the Bush-league

The Bush administration has not demonstrated a high degree of understanding of basic scientific principles or knowledge of the bases of science in their time in office.  From global warming to intelligent design, the members of the Bush-leagues seem to be existing some time circa 1600.  Today's New York Times has an editorial criticizing the EPA's rejection of new standards for soot emissions.  According to Stephen Johnson, EPA's administrator, the evidence remains "insufficient" to support new standards, despite the overwhelming recommendations of EPA's own science advisors and scientists.  It sometimes appears with the Bush administration that the only science that would be good enough to convince them that they should do what they were disinclined to do for policy reasons would be scientific findings that rode in on a golden chariot from the heavens.  The Bush-leaguers need a lot more science, and a little less policy in their science-policy.  See Editorial Here.

Forensics Fired

I watched the National Geographic special last night, "Naked Science: Forensics Under Fire."  It was, as I anticipated, well worth watching.  They concentrated on arson and firearms identification (both ballistics and bullet lead comparisons).  The show was extremely critical of forensic science as it is practiced today, which is not surprising, since there is so much to be critical about.  It was only an hour long, however, so it is understandable that the producers had to focus on a couple of subjects, though they cast their aspersions widely.  My only quibble was the show's coverage of a National Institute of Justice study that was commissioned to prove that firearms identification experts can do what they claim they do.  As an intial matter, of course, research should not be designed to prove that something is true, but should be carried out to test whether something is so or not.  More problematic, however, the research involved computer evaluations of whether bullets fired from the same gun are distinguishable from bullets fired from different guns.  The researchers found that, indeed, this was the case, and concluded that thus firearms experts could validly determine whether a bullet came from a particular gun.  There is so much wrong with using this methodology to support the asserted claim that I wouldn't know where to start.  But surely, whatever this research might demonstrate, it is not that firearms examiners can validly "match" an unknown bullet to a known gun.

In the end, however, this program offers an excellent introduction to the problems endemic in forensic science.  The program's ultimate conclusion is, without question, worthy of attention.  Forensic scientists cannot rely on years of experience to support their claims;  their hypotheses must be subjected to rigorous scientific test.
--- DLF

Forensics Under Fire

I wanted to move this to the front, since the show airs this evening.

Forensic science is the subject of a national geographic production to be aired on October 12th.  The notice follows.

We wanted to let you know that "Naked Science: Forensics Under Fire" is scheduled to air on the National Geographic Channel on Thursday, October 12 at 10:00 p.m. ET/9:00 p.m. CT. Produced by Jon Siskel and Greg Jacobs for Towers Productions, the show takes a close look at recent challenges to the reliability of forensic science, and how the field is responding to those challenges.

It should be well worth watching.
--- DLF

Truthiness in Science

The new group, Scientists and Engineers for America, already a great success though still in its infancy, reached a new high when it was the subject of Stephen Colbert's Word segment, which can be seen here.
--- DLF

Toxic Torts

Carl Cranor, a professor at the University of California, Riverside, has a new book out, entitled "Toxic Torts: Science, Law and the Possibility of Justice."  The description from the publisher, Cambridge University Press, follows:

The U.S. tort, or personal injury law, cloaked behind increased judicial review of science, is changing before our eyes, except we cannot see it. U.S. Supreme Court decisions beginning with Daubert v. Merrell-Dow Pharmaceutical altered how courts review scientific testimony and its foundation in the law. The complexity of both science and the law mask the overall social consequences of these decisions. Yet they are too important to remain hidden. Mistaken reviews of scientific evidence can decrease citizen access to the law, increase incentives for firms not to test their products, lower deterrence for wrongful conduct and harmful products, and decrease the possibility of justice for citizens injured by toxic substances. Even if courts review evidence well, greater judicial scrutiny increases litigation costs and attorney screening of clients, and decreases citizens’ access to the law. This book introduces these issues, reveals the relationships that can deny citizens just restitution for harms suffered, and shows how justice can be enhanced in toxic tort cases.

Although I don't agree with many of the conclusions Carl reaches (I am a bigger Daubert enthusiast than he is -- though I share many of his political inclinations), his analysis is always informed and sophisticated.  His arguments are strong, if not always persuasive; but they are always worth listening to.
--- DLF

ELS Rankings

The folks at the Empirical Legal Studies Blog recently posted their 2006 ELS rankings of law schools.  See Here.  I am not entirely against the idea of ranking law schools, but one must wonder at the value of this particular one.  The methodology is an embarrassment.  The three factors chosen for analysis were:

--relative number of research faculty with social science doctorates

--relative number of research faculty with a secondary social science appointment

--per capita articles citing “statistic! /1 significan!” in Westlaw JLR since 1996

Needless to say, perhaps, but these factors represent a rather poor effort at operationally defining the subject of study, which presumably is, what schools excel in the area of empirical legal studies.  One would have thought that the purpose of such rankings would be to identify which schools were doing substantial (i.e., of significant quantity) valid research (i.e., of significant quality).  These variables offer little help in this regard.

The purpose of most rankings is to provide some audience with information that they might use.  Although U.S. News' rankings are mostly junk (although not as junky as the ELS Rankings), they provide a service to prospective law students who seek an index of "law school prestige."  Who is the audience for the ELS rankings?  I doubt that students who are interested in doing empirical scholarship would find the rankings of much help, or very persuasive.  I doubt that too many of such students will pick George Mason over Harvard, because the former is ranked second and the latter eighteenth.  I also doubt that too many empiricists would make job decisions based on such rankings; and, if they did, they would deserve exactly what they got.

These rankings, therefore, seem to be an excessive bit of navel-gazing.  I suppose it would be less worthy of comment if the gazing had been a little more clear-eyed.  But it is the height of irony that these meritless rankings were promulgated and promoted by legal empiricists.  Legal? perhaps.  Empirical? Not from where I'm standing.
--- DLF

Scientists for Informed Science Policy

A group of scientists and engineers has begun a new organization dedicated to supporting politicians who are committed to using good scientific research in forming public policy.  The group is Scientists and Engineers for America, and their website can be found here.   They outline their initial goals on their newly created Blog.   On their main webpage, they state as follows:

Today a group of scientists and concerned citizens launch a new organization, Scientists and Engineers for America, dedicated to electing public officials who respect evidence and understand the importance of using scientific and engineering advice in making public policy.
The principal role of the science and technology community is to advance human understanding.  But there are times when this is not enough.  Scientists and engineers have a right, indeed an obligation, to enter the political debate when the nation’s leaders systematically ignore scientific evidence and analysis, put ideological interests ahead of scientific truths, suppress valid scientific evidence and harass and threaten scientists for speaking honestly about their research.
We ask every American who values scientific integrity in decision-making to join us in endorsing a basic Bill of Rights for Scientists and Engineers.  Together we will elect new leadership beginning in 2006, and we will continue to work to elect reasonable leadership in federal, state and local elections for years to come.

It certainly sounds like a worthy cause.  The New York Times article describing the founders and their goals can be found here.
--- DLF

Student Edition of Modern Scientific Evidence

One perquisite of having a blog is self-promotion.  In that spirit, the new student edition of our four volume treatise, Modern Scientific Evidence: The Law and Science of Expert Testimony, is now available.  The student edition is a two volume, and reorganized, version of the bigger set.  One volume is dedicated to introductory subjects, including, among others, admissibility standards, research methods, statistics, toxicology and epidemiology.  The other volume is dedicated to subjects in the forensic sciences, ranging from DNA to latent fingerprint identification.  The announcement from Thomson/West Publishers follows:

West is pleased to announce the recent publication of Faigman, Kaye, Saks, Sanders and Cheng's Modern Scientific Evidence 2006 Student Editions: Standards, Statistics and Research Methods and Forensic Issues.
Judges and lawyers are not generally known for expertise in science and mathematics. Nor is science a subject given significant attention in American law schools. Times, however, are changing. An ever-increasing percentage of the average lawyer's caseload involves scientific and technical evidence. Indeed, it is the rare case that does not involve experts. Following the landmark case of Daubert v. Merrell Dow Pharmaceuticals, Inc., federal courts, and many state courts, mandate that trial court judges operate as gatekeepers in regard to expert evidence. The lawyers who practice before them will need to make the arguments for and against admission of disputed expertise. And if the disputed expert opinion is admitted, the lawyers must have the wherewithal to cross-examine that testimony. If lawyers are going to be prepared for the practice of law in the twenty-first century, they need to develop a basic understanding of statistics and science.
Standards, Statistics and Research Methods and Forensic Issues are special student editions of a much larger work intended for a professional audience, our four volume treatise MODERN SCIENTIFIC EVIDENCE: THE LAW AND SCIENCE OF EXPERT TESTIMONY (2005). The student editions are available separately. Standards, Statistics and Research Methods focuses on standards, statistics and research issues surrounding expert evidence, and Forensic Issues is devoted to subjects in the forensic sciences. These volumes will be effective either standing alone or as companions to regular texts in a variety of classes. More fundamentally, we hope that these volumes will be used to begin the process of educating lawyers and judges regarding the scientific method in law school.
Science is a tool that the law can and must use to achieve its own objectives. Science cannot dictate what is fair and just. But science has become, and will forever more be, something upon which the law must sometimes rely to do justice.

---DLF

Clueless Fingerprints

The Weekly Detail, a newletter for the latent fingerprint community, reported a talk by Steve Scarborough in today's edition.  The talk, the first of two parts, was given to a large group of latent examiners.  You can subscribe to The Weekly Detail here.   Since it appears to be taken from an oral presentation, the talk rambles somewhat and is hard to appreciate from a distance.  Nonetheless, it is instructive, since it represents some of the thinking (or lack thereof) that is going on in this community.  His main argument appears to be in response to those who doubt the "uniqueness" of fingerprints.  Along the way, he seeks to defend claims of "infallibility" in the process of fingerprint identification, though he argues that such claims do not mean that examiners don't make mistakes.  The two issues of uniquenenss and error rates must be kept separate, though Scarborough does not always accomplish this well.

First of all, on the question of uniqueness.  Most critics do not challenge the uniqueness of fingerprints.  It is a red-herring; it is both scientifically uninteresting and legally irrelevant.  The uniqueness of fingerprints says absolutely nothing, NOTHING, about the ability of examiners to reliably and validly make fingerprint identifications between partial latent fingerprints and the known prints of a suspect or defendant.  In theory, every person's face is unique, but this fact, if it is so, does not tell us whether reliable and valid identifications can be made when comparing the nose and ear of an unknown person to the full face of a known person.  Empirically, the hypothesis that fingerprints are unique is separate and largely unrelated to the hypothesis that fingerprint identifications can be made from partial latent prints. 

Please, can we all just stop talking about whether fingerprints are unique.  Nothing follows from the fact, if it is so, that they are unique.  I, for one, willingly (nay, enthusiastically), concede for the sake of all further argument that fingerprints are unique.  Now, let's move on.

The second issue presented, and the one of great legal significance, is the error rate of latent print examination.  Claims of "infallibility" pertain to whether fingerprint examiners are 100% accurate.  To his credit, Scarborough admits that fingerprint examiners make mistakes, despite apparent comments to the contrary:

In all the training classes and presentations and testimony, the FBI has never once said that there are no mistakes made by fingerprint experts. In fact the FBI, in warnings about effective verification, mentions mistakes that they are run across in submitted cases from local agencies. The FBI has always promoted verification, consultation and double checks to assure that no mistakes in fingerprint identifications are made.

The fact that mistakes are possible, then, requires some level of quality control, which might or might not be effective.  It should also result in attempts to measure the rate of those errors.  On the general issue, he states as follows:

The FBI instructors stress verification and other quality control measures.  They promote and teach verification to prevent mistakes. If people didn’t make mistakes with regard to Fingerprints ... then we wouldn’t need verification.  But we all know that human beings make mistakes, and it goes without saying that humans are not infallible. The assumption that when the FBI fingerprint expert says that they are 100% certain about the ID, that they are implying that they don’t make mistakes, is a grand leap of logic.

At the end of the above quote, the waters get muddied.   Scarborough is saying that a claim of 100% certainty by a latent print examiner is not a claim that they are 100% accurate.  Fair enough.  But what, then, is the claim of 100% confidence based upon, if not some idea that the error rate associated with the technology he or she used is "vanishingly small."  Indeed, I don't know of any bona fide scientist who would claim 100% confidence in a technique/process/machine that itself did not have 100% accuracy.  But, in any case, how do examiners know that their error rates are so low that they can have 100% confidence in their conclusions?  It cannot be made on the basis of the uniqueness-of-fingerprints hypothesis, since that hypothesis has nothing to do with the hypothesis of latent examiner validity (see above).  It is not based on published research, since precious little exists.  It cannot be based on experience -- other than casual anecdote -- since no systematic attempt has been made to catalogue errors.

So, I am very heartened to see that a prominent latent examiner has admitted the existence of measurable error rates associated with latent fingerprint procedures.  It's about time that researchers began to actually measure those error rates.
--- DLF

 

Women in Science

A new report by a panel convened by the National Academies of Science finds that institutional barriers, not innate differences, explain the "relative dearth of women in the upper ranks of science."  The report can be found Here.   Today's New York Times story on the panel report can be found Here.

New York Times columnist John Tierney dismisses the Academy's report as little more than an embarrassing PC tract.  See Here.

Special Admissibility Rules

Occasionally states will establish special admissibility criteria different from, and generally more liberal than, those that would be imposed by the courts. In Commonwealth v. Conklin, 897 A.2d 1168 (Pa. 2006) the defendant was a convicted sex offender classified as a "sexually violent predator" (SVP). Under Pennsylvania law, such a person suffers from a "mental abnormality or personality disorder that makes the person likely to engage in predatory sexually violent offenses." The defendant objected to the qualifications of the state’s expert, a clinical social worker, who testified that based on his "diagnostic impressions" that the defendant fit this clinical diagnosis. However, the Supreme Court held that the state was not required to provide the testimony of a licensed psychiatrist or psychologist because the statute in question stated that the opinion of a qualifying "criminal justice expert" suffices. As to a Frye challenge that the statute's admissibility criteria for expert testimony on SVP status "does not square with prevailing standards and methodology in the psychological and psychiatric diagnostic communities," the court quotes an earlier opinion that held the statute simply does not require the state to meet the diagnostic standards that are commonly accepted in the mental health field. Absent this statutory provision, it is not clear whether the court would have found the expert to be qualified to make this diagnosis.

Setting aside the question of whether there is research supporting the proposition that anyone can make a SVP diagnosis with any accuracy, the case raises the interesting question of how often states pass specific statutes or rules of evidence designed to sidestep ordinary admissibility criteria. See, for example, West's Ann.Cal.Evid.Code § 1107, admitting testimony on the effects of "intimate partner battering."

It would be useful to have a census of such statutes to better understand the circumstances in which the legislature feels compelled to take this step. I would be very interested in hearing about such statutes.

JS

Paying for Pollution

One of the basic reasons why we pollute the planet at the rate we do is quite simple.  We seemingly don't have to pay any of the costs.  If I throw my garbage over my fence onto my neighbor's property, I don't bear the costs associated with cleaning it up -- at least until my neighbor comes over to punch me in the nose.  Similarly, if I dump my garbage in the public domain, I am not forced to internalize any costs for the damage I cause.  The principle operates similarly when a State produces air pollution that causes acid rain in another state.  Effectively, the state is simply dumping its garbage over its fence.  If we actually had to pay for the costs (as we inevitably do in effects such as global warming), we might pollute less and make better choices.  This very basic idea has caught on in Europe, where companies are increasingly paying for the damage they do to the environment in the form of offsets.  If a company's employees are responsible for X amount of carbon dioxide emissions, due to their air travel, the company pays an equivalent amount in nonpolluting energy investments.  It's not perfect, but it's better than the status quo.  See Article Here.   It's also better than a punch in the nose, which appears to be what "mother nature" is going to give us if we continue to pollute at current rates.
-- DLF

"Eyecheck" Drug Screening

According to officer.com, West Virginia will soon be using a new roadside drug screening device.  See Here.   The device is called the "Eyecheck Pupillometer."  Seriously.  It looks like a pair of binoculars and is designed to identify those who are impaired, either because of drug use or simply fatigue.  According to the manufacturer's website, "The subject simply looks into the unit. A light flashes - the pupil reacts to this stimuli, first constricting and then re-dilating. EyeCheck™ measures and evaluates this response…."  See Here.   A quick Google search indicates that several police departments are considering using the device, and several, like West Virginia, are moving forward with its use.  Most discussion on the web promotes its "reliability" for identifying impaired drivers, but none that I've found cite actual research reporting error rates for the device.  Not surprisingly, despite this lack of detail regarding its scientific validity, law enforcement communities trumpet its potential value in screening drivers, since it is quick, easy, and non-invasive.  However, since those who fail such tests might be arrested and be required to give a blood test, the false positive rate for such devices ought to be known before they are approved for general use -- or would be sufficient to support an arrest.  See Article discussing uses of device here.
--DLF

A Conversation with James Lovelock

Here's a conversation worth listening to....  Lovelock certainly does not have all of the answers, but he's asking most of the right questions.  See Here.

E.O. Wilson's Newest

Something always worth celebrating is the publication of a new book by E.O. Wilson.  His latest is "The Creation: An Appeal to Save Life on Earth."  Its theme is conservation, and Wilson attempts to bridge the divide between science and religion by finding common cause in our shared existence.  Wilson writes, "Let us see, then, if we can, and you are willing, to meet on the near side of metaphysics in order to deal with the real world we share."   Wilson is an extraordinarily graceful and elegant writer of science.  From today's N.Y. Times: "'The Creation' is the wise and lovely work of a truly learned man, filled with a spirit that readers of every stripe will recognize as reverence."  (See full review here.)

Threshold for Admissibility in CERCLA and FELA cases

An interesting question arises as to whether there is a lower standard of causation in some areas and whether this should impact admissibility rulings. This issue has arisen in CERCLA cases, Kalamazoo River Study Group v. Rockwell Int'l Corp., 171 F.3d 1065 (6th Cir.1999); Goodrich v. Betkoski, 99 F.3d 505 (2d Cir.1996); Freeport–McMoran v. B–B Paint Corp., 56 F.Supp.2d 823 (E.D.Mich.1999); and in FELA cases, Claar v. Burlington Northern R.R., 29 F.3d 499 (9th Cir.1994); Savage v. Union Pacific R.R., 67 F.Supp.2d 1021 (E.D.Ark.1999). Courts have generally concluded that admissibility criteria are not relaxed in these cases.

A recent Indiana case, however, appears to waffle on this issue. In Norfolk Southern Railway Co. v. Wagers, 833 N.E.2d 93 (Ind. App. 2006), the decedent’s estate alleged that his lung cancer was caused by his workplace exposure to asbestos fibers, diesel fumes and exhaust, and herbicides. Wagers also had a significant history of smoking cigarettes. At deposition, plaintiff’s expert testified that he had no knowledge about the frequency with which Wagers may have encountered or used materials containing asbestos and that he had no quantitative data about Wagers's exposure to asbestos and diesel fumes. Nevertheless, his testimony was admitted. According to the appellate court, "The trial court acknowledged Norfolk's ‘compelling’ arguments that Parkinson's opinion should be excluded under Evid. R. 702(b). However, it found controlling the Estate's argument that actions under FELA require less evidence of causation to establish liability than ordinary negligence actions and that a relaxed standard of causation in FELA actions also lowers the threshold of admissibility for expert testimony. Norfolk contends that the trial court erred in determining that this lower standard of admissibility applies in FELA cases. We need not decide whether a lower standard of admissibility applies, however, because Parkinson's testimony meets the requirements of Evid. R. 702(b)"

The appellate court’s protestations to the contrary notwithstanding, it is hard to imagine that most judges applying a Daubert-like test would permit an expert to testify on such a skimpy dosage and exposure record.

JS

Crikey!

The New York Times published a wonderful "appreciation" for Steve Irwin, the Crocodile Hunter, who died this past week when he was stung in the heart by a stingray.  Lawrence Downes wrote that Irwin would be missed particularly for his talent at bringing the wonders of nature to viewers around the world.   (See full article here.)  Irwin was no scientist, but he undoubtedly inspired many young viewers to become scientists.  Mr. Downes observed:

It was easy to parody Mr. Irwin’s boisterous shtick, and many people did. It is easy, too, to shake our heads at the relentless peddling of nature as TV entertainment, and to lament that the only animals people ever bother thinking about are either fuzzy-cute or man-eating. It is all too obvious that Mr. Irwin was no biologist, that exploring the world on cable TV is a lot different from actually plunging into it, that wild animals really are dangerous, and blah blah blah.

But there are far worse ways to view the natural world than through the eyes of a young child, and Mr. Irwin offered a far more temperate version of the classic 6-year-old-boy approach, which is to confront a wild animal, marvel at its strength and ferocity, and then try to hit it with a rock. For Mr. Irwin, wild nature was something to wonder at, and he did so with an enthusiasm indistinguishable from love. Animals — even deadly ones — are good, poachers are evil, and, crikey, that’s pretty much it.

Call that simple-minded, call it dumb, but it resonates. Future environmentalists and conservationists have to come from somewhere.

Popularizers, like Steve Irwin -- and others inlcluding Carl Sagan  (who WAS a first-class scientist) -- have always received a bad rap.  But it is the Irwins and Sagans of this world -- who ignite the imaginations of the young, and relieve the anxieties of all of those who fear the complexities of the science -- that are needed to improve the science literacy of the general public.  Given the current state of knowledge of science among lawyers and judges, we could use a few Irwins to take up the challenge of popularizing science in the law.

Judicial Gullibility

In United States v. Mahone, a July decision from the United States Court of Appeals for the First Circuit, the court agreed with the trial judge's decision that a forensic specialist in footwear impressions was qualified because "she stated that she had made more than 11,000 footwear comparisons [while] she had worked as a 'latent impressions' specialist for more than two years.  Giving the expert the benefit of the doubt on her years of experience, this means that she did fourteen comparisons a day every working day for three years.  This is a little hard to believe, yet the court never raised an eyebrow at such a patently ridiculous claim.  She also never said how many of the 11,000 she got right.

Such silliness is not limited to the First Circuit.  In a 2000 case, Sullivan v. Ford Motor Co., the federal court in Manhattan admitted a safety engineer's report following a severe accident.  Based on the expert's experience, the court found both that he was qualified to testify and that the basis for his testimony was reliable.  The court explained as follows:

The fact that [the expert] did not know all of the precise details about the accident at issue in this case does not indicate that his expertise based on his experiences investigating approximately 15,000 road accidents, preparing approximately 10,000 reports based on these investigations, witnessing approximately 100 test crashes, authoring studies based on his observations, as well as his education in the area of physics, mechanical engineering and law, would not be helpful to the jury in determining this factual issue.

Brief reflection on the expert's claimed experience suggests that it is somewhat incredible.  To have investigated 15,000 accidents, he would have had to visit approximately two accident scenes every working day for 30 years.  This leaves little time to write 10,000 accident reports.
-- DLF

Mental Illness, Mental Abnormality, and Insanity

The law of behavioral responsibility, on both the criminal and civil sides of the docket, is in a state of moral and empiricial disrepair.  There are a host of different theories that States use to determine when someone should be "excused" from conduct that otherwise would be criminal.  (Of course, the very low number of defendants who successfully claim "insanity" are not "let go," but often spend the remainder of their days in mental hospitals.)  In the recent case of Clark v. Arizona, the Supreme Court usefully summarized the many different theories employed today:

The main variants are the cognitive incapacity, the moral incapacity, the volitional incapacity, and the product-of-mental-illness tests.  The first two emanate from the alternatives stated in the M'Naghten rule. The volitional incapacity or irresistible-impulse test, which surfaced over two centuries ago (first in England,  then in this country), asks whether a person was so lacking in volition due to a mental defect or illness that he could not have controlled his actions. And the product-of-mental-illness test was used as early as 1870, and simply asks whether a person's action was a product of a mental disease or defect.  Seventeen States and the Federal Government have adopted a recognizable version of the M'Naghten test with both its cognitive incapacity and moral incapacity components.  One State [Alaska] has adopted only M'Naghten's cognitive incapacity test, and 10 (including Arizona) have adopted the moral incapacity test alone.  Fourteen jurisdictions, inspired by the Model Penal Code, have in place an amalgam of the volitional incapacity test and some variant of the moral incapacity test, satisfaction of either (generally by showing a defendant's substantial lack of capacity) being enough to excuse.  Three States combine a full M'Naghten test with a volitional incapacity formula.  And New Hampshire alone stands by the product-of-mental-illness test.  The alternatives are multiplied further by variations in the prescribed insanity verdict: a significant number of these jurisdictions supplement the traditional "not guilty by reason of insanity" verdict with an alternative of "guilty but mentally ill."   Finally, four States have no affirmative insanity defense, though one provides for a "guilty and mentally ill" verdict.  These four, like a number of others that recognize an affirmative insanity defense, allow consideration of evidence of mental illness directly on the element of mens rea defining the offense.

In Clark itself, the Court held that the Arizona rule of  "moral incapacity," was not unconstitutional.  Under this rule, an Arizona defendant can claim insanity only if a mental disease or defect leaves him unable to understand that his action was wrong.  Moreover, the Clark Court also held that the Arizona rule that evidence of mental incapacity was admissible only to show insanity, and could not be admitted to negate mens rea, did not violate the Constitution.  (For an excellent discussion of this aspect of the Clark ruling, see Sherry Colb's analysis on Findlaw.com -- see here.

The Clark Court held that this patchwork of approaches to criminal responsibility was essentially a product of our federalist system, which defers greatly to the judgment of the States.  But, at some point, the Constitution should require a certain basic minimum regarding what states of mind are necessary to assume responsibility over behavior.  Professor Colb, for instance, argues in the piece cited above that mental states that negate mens rea, at the least, should qualify under basic standards of due process.  Perhaps, more importantly, the Constitution should contain some basic conception or philosophy of human behavior.  After all, much of the basic rationale for criminal punishment follows from the view that people have free will and thus are responsible for the consequences of their behavior (at least, for those results that were intended, known, or foreseeable).

But this raises an even deeper contradiction in the Supreme Court's, and thus the Constitution's, views of behavioral responsibility.  On the civil side of the docket, the Supreme Court held in a couple of cases that sexual aggressors can be committed indefinitely if a State demonstrates that they are mentally abnormal and likely to be violent.  In the cases of Kansas v. Hendricks and Kansas v. Crane, the Court developed a definition of mental abnormality that is inconsistent with much of the jurisprudence that it has accepted on the criminal side.  According to the Court, the reason why a "mentally abnormal" person can be civilly committed is that the twin pillars of the criminal system -- retribution and deterrence -- are not implicated when someone is mentally abnormal.  The Court defined "mental abnormality" as "substantial lack of volitional control."  The reasoning is straightforward:  if someone cannot control their behavior, then they should not be punished for their behavior (i.e., retribution is not implicated as a goal), and they will not be deterred from acting criminally.  Yet, as the above discussion of insanity makes clear, this volitional control argument is employed by very few states in criminal cases and is generally thought to be unworkable in practice.  How, after all, does one distinguish between behavior that someone cannot control and behavior not controlled?

In any case, what is clear is that the Supreme Court has accepted different versions of human agency on the criminal and civil sides of their docket.  Someone who lacks volitional control, therefore, can constitutionally be held responsible for his conduct and be put in prison.  When that person emerges from prison, he can then be incarcerated in a mental hospital idefinitely, because he lacks volitional control.  I suppose that given the stark political realities of the situation, this outcome should not be so surprising.  The defendant is locked up on both sides of the equation.  But the Constitution is not supposed to trade in stark political realities, and should have a more sophisticated understanding, or at least a more consistent definition, of human agency.
-- DLF

Global Warming & Bush's Reading List

The Washington Post has a very good review of James Lovelock's new book about global warming, "The Revenge of Gaia: Earth's Climate Crisis and the Fate of Humanity."  [See Here]  To be sure, Lovelock tends to the extreme, at least in his colorful descriptions of, and basic nihilism about, global warming.  But his basic view is shared by most mainstream scientists and even if his predictions are off by a substantial margin, the prognosis remains bleak.

When it comes to science policy, three factors in particular must be considered.   The first is the quality of the science that supports a particular prediction, the second is the gravity of harm that will occur if the prediction occurs, and the third is the cost associated with remedying or avoiding the harm.  Global warming presents a particularly challenging issue given these three considerations.  Most mainstream scientists agree that the science is solid, though it is complex and not unassailable.  The consequences of global warming, especially if the most dire predictions prove true, will be catastrophic; and even many of the most modest forecasts predict very severe effects.  Finally, as Lovelock believes, there is some question whether there is very much that can be done to avoid the inevitable tragedy that lies on our collective horizon.  Admittedly, therefore, global warming presents no simple problem for policy makers, even those most knowledgeable about the science.  One thing is for sure, however, policy makers ignorant of the science are unlikely to handle the complexities of this issue very well.  Perhaps George Bush should consider adding Dr. Lovelock's book to the 60 books he claims to have already read this year.  It may not be as compelling as "Pride and Prejudice," but there are valuable lessons to be learned nonetheless.
-- DLF

Women Clerks at THE SUPREME COURT

A subject of great interest around the blogs these days is the low number of women clerks hired by Supreme Court justices this year.  It is the subject of a story by Linda Greenhouse in today's New York Times.  (See here)  Apparently, the number of female clerks hired this year fell by half from a year ago.  Out of 37 clerkships for the new term, only 7 are women.  Trying to downplay the significance of this fact, Justices Souter and Breyer, both with a history of hiring many female clerks, attributed the low number to "random variation."  This proposition, of course, is testable.  According to the story in the Times, 37 clerks were hired from a population of applicants that contained approximately 1/3 women.  (This 1/3 number is suspect, since more than half of all graduates today are women.  If the number is higher, then the expected number of clerks would be higher as well -- thus strengthening the basic conclusion I reach below.)  All things being equal, therefore, we would have expected the justices to hire approximately 12 female clerks.  They hired 7.  The question, therefore, is what is the likelihood that this departure from what is expected would happen by "random variation."  According to the Supreme Court's own precedent, Castaneda v. Partida, this can be derived by first determining the standard deviation for this binomial distribution (male/female).  The standard deviation here is the square root of the product of (1) the total size of the group (37), times (2) the percentage of women (1/3), times (3) the pecentage of men (2/3).  A little simple math gives us a standard deviation of 2.86.  The obtained number of women this year, therefore, is almost two standard deviations from the expected number.  According to the Court in Castaneda, "if the expected value and the observed number is greater than two or three standard deviations," chance fluctuations are an extremely unlikely explanation.  Certain caveats must be noted.  First, the sample is small here, which affects how confident we can be in drawing any conclusion.  Also, the departure was less than two standard deviations, so it does not quite meet the arbitrary standard created by the Court.  Finally, while the data suggest that chance is not a good explanation, they cannot tell us what alternative hypotheses might explain the disparity.  So, are Justices Souter and Bryer correct?  Is "random variation" a good explanation for the small number of female clerks?  My answer is, probably not.  But more research would be needed to say what is causing the  disparity observed.  I am sure the Justices will welcome further research on this question.
-- DLF

Breath Analyzers as Black Boxes

     Breath analyzers designed to test drivers’ level of intoxication are black boxes.  Breath goes in and an estimated blood alcohol concentration (BAC) reading comes out.  Typically, states require periodic testing of these instruments to assess their accuracy.  The testing involves using a sample with a known alcohol concentration to assess whether the instrument is properly calibrated.  Defendants from time to time attempt to force the state to do even more to certify every step of the operation.  In State v. Ensey, 881 A.2d 81 (N.J. 2005), the defendant moved to suppress the results of a breath test because the state failed to provide a witness who could testify concerning the preparation of the mixture used to calibrate the breath analyzer used in this case. The court rejected the defense argument that this was required to lay an adequate foundation for the admission of the test results.

    A more interesting development is a flurry of decisions in Florida on the question of whether the state must turn over to the defense the software used by the breath analyzer to calculate an individual’s alcohol content.  Breath analyzers must make at least three separate calculation in order to provide a BAC.  See Patrick Barone, Commentary: Unlocking the Mystery Behind Breath Testing: The Right of Access to Source Codes. 4/ 17/ 06 Mich. Law. Wkly, 2006 WLNR 9002476. 

    First, the machine must measure the level of alcohol in the breath.  This is done by measuring the resistance of an infrared light beam as it passes through a sample chamber containing the individual’s breath.  The theory behind this methodology is that ethanol absorbs infrared light and, therefore, the loss of energy in the beam may be attributed to the level of alcohol in the sample. 

     Second, the breath alcohol level (BrAC) must be used to estimate BAC.  This is done using Henry’s Law: At a constant temperature, the amount of a given gas dissolved in a given type and volume of liquid is directly proportional to the partial pressure of that gas in equilibrium with that liquid.  In this context the liquid is blood and the gas is breath in the closed system of the lungs. The typically accepted ratio used in law enforcement is 2,100 to 1.  For every molecule of alcohol in the breath (BrAC) there are 2,100 molecules in the blood (BAC).  This, of course, is the ratio under ideal conditions and in the past there has been a fair amount of litigation over the appropriate constant to apply.

     The third calculation relates to the proper application of Henry’s law.  The law applies to gas in equilibrium with the liquid.  This is the case only with respect to alveolar (deep lung) air.  In an attempt to obtain alveolar air, officers are routinely asked the suspect to blow hard into the machine. Under normal conditions, when there is no alcohol present except that in the lungs, as one blows into the machine the breath alcohol level rises and then levels off as alveolar air passes through the machine. That is, the highest BrAC is found in alveolar air.  If one does not blow hard enough alveolar air may never reach the machine, but if the only alcohol present is that evaporating into the lungs from the blood the result is a reading that underestimates one’s true BAC.  Problems arise, however, if there is other alcohol present. If one were to rinse one’s mouth out with a glass of bourbon right before taking a test some of this mouth alcohol would evaporate when taking the test and thus the machine would return a reading that overestimates BAC. 

      In order to avoid this difficulty, many states require that an officer observe the defendant for 15 or so minutes prior to administering the breath test to be certain the individual has not put any alcohol into his mouth or done anything else such as belch that would affect the reading.  Failure to observe the individual during this period occasionaly leads to the exclusion of the subsequent test. See State v. Korsakov. 34 S.W.3d 535 (Tenn. Crim. App. 2000). 

     The equipment itself is designed to detect this problem and to return an “invalid sample” message when some other source of alcohol seems to be present. This is accomplished through “slope detection.” The machine attempts to detect a rising “slope” of greater and greater BrAC as the individual blows into the machine and when it does not detect a slope it should return the “invalid sample” message. When calibrating an instrument, the state should test to see if the slope detector is working properly.  However, there is some question as to whether this slope detection feature always works correctly.  See Michael Hlastala, Wayne Lamm and James Nesci, The Slope Dectector Does not Always Detect the Presence of Mouth Alcohol, 20-MAR Champions 57 (March 2006). 

      In a number of recent Florida cases, defense attorney’s have asked for the computer code by which the breath analyzers make these calculations. They argue that without access to the code there is no way to know if the results of the machine would pass muster under a Daubert or Frye reliability analysis. Several judges have found that defendants are entitled to this code.  See Paul Quinlan, Surprise Court Ruling threatens to Nullify Results of DUI Tests, 11/4/05 Sarasota Herald Trib. A1, 2005 WLNR 17892443. The manufacturer of the equipment used in Florida, the Intoxilyzer, has refused to produce the code which it says is a trade secret. 

    This litigation raises a pair interesting questions concerning all equipment used in forensic testing.  First, how far back may the parties go in an attempt to deconstruct the scientific knowledge proffered by an opponent?  Second, to what extent should the results of an instrument be admitted if it passes a reliability testing protocol even when we are not certain exactly why it is able to pass the protocol?

JS

News from the Fingerprint Community

For news straight from the community of experts who specialize in fingerprint identification, you can subscribe to their weekly newsletter here.  It's an informative bulletin that Kasey Wertheim sends to your email in-box each Monday morning.  As their webpage explains, "The purpose of the Detail is to provide Latent Print Examiners with another avenue to receive and relay current information regarding our field."  It provides lots of great information and, while it is obviously tailored to the professional community of fingerprint examiners, it does not shy away from including news and comments that are critical of the field.
--- DLF

Helping Legal Actors with Bayes’ Theorem

The importance of understanding base rates and Bayes’ Theorem cannot be overstressed, particularly in the case of many types of medical and scientific testimony. The importance of base rates is seen in the following problem: A disease occurs in 1% of the population, and a test has been developed which has an 80% accuracy rate (i.e., if you have the disease, there is a 80% chance the test will pick it up), and a 9.6% false positive rate (i.e., if you don’t have the disease, there is a 9.6% chance of getting a positive result anyway). Sam tests positive for the disease. What is the probability that Sam has the disease?

The general inclination is perhaps to say 90.4%, because the false positive rate is 9.6%. This conclusion, however, is wrong because it does not account for the rarity of the disease in the general population. (As doctors are often trained to think, if you hear hoofbeats, think horses, not zebras.) Using Bayes’ Theorem—and here I will spare the reader the mathematical details—one can show that the probability that Sam has the disease is 7.8%. Intuitively, this is because given the rarity of the disease, it is more likely that Sam is actually one of the false positives than one of the people with the disease. Short of being a math genius, however, crunching the numbers is extremely difficult to do intuitively, and merely plugging values into Bayes’ formula has a certain mystical quality that might make jurors (or judges) skeptical.

Psychological research by Gigerenzer & Hoffrage, however, suggests that people find analyzing the problem from a frequentist perspective far easier than from the probabilistic perspective shown above. We can see this by transforming the example above to series of frequencies: A disease afflicts 10 out of 1000 people in the population. For people with the disease, 8 out of 10 will have positive test results. For people without the disease, the test will still (erroneously) yield a positive result 95 out of 990 times. Sam tests positive for the disease. What is the probability that Sam has the disease?

The answer follows far more simply. Out of a population of 1000 people, 8+95=103 people will test positive. And of these 103 people, only 8 actually have the disease, so the probability that Sam has the disease is 8/103 = 7.8%.

Gigenrezer and Hoffrage write that only 16% of people presented with the percentages got the correct answer, compared to 46% of those presented with the frequencies.

This research is just one example of the many ways that psychology can help jurors and other legal actors grapple with scientific data and make better decisions. The underlying math is the same, but as we lawyers know, presentation is often half the battle (if not more). I’m indebted to Michael Bishop and J.D. Trout’s fascinating book, Epistemiology and the Psychology of Human Judgment (Oxford 2005) for calling my attention to this work and providing the above example. In their book, Bishop & Trout defend a new interdisciplinary approach to epistemology that takes advantage of current psychological research and argue how epistemology should be reconceived to help people make better everyday decisions.

--EKC

The Perils of Profiling

Professor Bernard Harcourt has an interesting op-ed in today's New York Times regarding the Transportation Security Administration's intention to expand behavioral profiling at the Nation's airports.  [See here]  He questions the validity of such techniques and recommends a straightforward thorough search of each passenger as a more effective solution.  I agree.  But I would add that there is another danger to adoption of such profiles.  They, in fact, tend not to narrow the population worth targeting for greater intrusion, they expand it.  Experience with behavioral profiles of the past, especially drug courier profiles and hijacker profiles, indicates that just about any behavior eventually finds its way into the profile's definition.  This means that law enforcement personnel are granted a large measure of discretion under the cover of a purportedly objective test.  For instance, courts have upheld searches of suspected drug couriers on the basis of a DEA profile that listed suspicious behavior as including (1) getting off an airplane first (United States v. Millan (8th Circuit)), (2) getting off an airplane in the middle (United States v. Buenaventura (2d Circuit)), and (3) getting off an airplane near the end (United States v. Mendenhall (S.Ct.)).  Other suspicious activity identified in court opinions includes (1) carrying a large heavy bag, (2) carrying little or no luggage, (3) paying for the ticket in cash with large bills, (4) paying for the ticket in cash with small bills, (5) paying for the ticket in cash with a combination of large and small bills, (6) leaving the airport by taxi, (7) leaving the airport by hotel courtesy van, (8) leaving the airport by private transportation, and so on.  The reader, I am sure, gets the point.  The problem with behavioral profiles is that they actually permit screening personnel to pursue hunches and intuition, possibly based on illegitimate if not unconstitutional bases, but to hide behind scientific claims of accuracy.  In the past, courts have not demonstrated either the inclination or the capacity to demand valid data to support reliance on behavioral profiles.  It is not that such profiles could not prove to be an effective law enforcement tool, but that they never are proved to be effective.  If TSA goes forward with its plans to step-up use of behavioral profiles, courts must demand the data that would support their continued use.
-- DLF

What's wrong with "near-match" DNA database searches?

This week, USA Today reported that the FBI will perform “near-match searching” of CODIS, the Convicted Offender DNA Index System. One might wonder why would police want to know the names of individuals whose DNA profiles fail to match those from samples from crime scenes or rape victims? The answer is simple genetics -- a near match implies that a close relative might be the source of the crime-scene DNA. Police in the United Kingdom have scored several significant successes with the technique. In the words of one official there, "We're having a positive effect on cases (and) preventing additional victims.  What's wrong there?"

Plenty, says Tania Simoncelli, who studies DNA database issues for the ACLU. In her view, “It's the worst kind of privacy intrusion.” Really? Worse than breaking into a suspect’s home and ransacking it for evidence?  Worse than installing a hidden video camera in a bedroom?  Worse than reading my mail or eavesdropping on my telephone calls?  Worse than breaking into a psychiatrist’s office to obtain a doctor’s files and notes?

OK, maybe there are worse invasions of personal privacy, and the ACLU is just engaging in the equivalent of campaign rhetoric here. The question is still what, exactly, is wrong with “near-match searching”? What valid privacy interest can a brother of a convicted offender assert to stop the police from using lawfully acquired information to develop a lead that points to him as a possible culprit? Surely the police can show a mugshot of the convicted offender to a woman who has been raped. If the woman reports that the man who raped her looked a lot like the photo, what is wrong with investigating to see if the brother, who closely resembles the mugshot, might be the rapist? Or suppose that the police question a suspect, who says, “I didn’t do it, my no-good brother did.” The brother might well be upset when the police come knocking on his door, but it is hard to claim that the intrusion on his “privacy” is unwarranted.

What is different when the investigative lead comes from the brother's DNA rather than his face or his mind? --DHK

The Continuing Monkey Wars

The New York Times is reporting today that evolutionary biology has been removed from the list of acceptable fields of study that are eligible for low-income federal grants.  [See story here]  Although the Department of Education claims that it was a clerical error, albeit an extraordinarily convenient one (given the Administration's beliefs about science), the omission is deeply troubling.  The error, no doubt, will be quickly corrected.  But it can be chalked up as one more instance of this Administration's scientific illiteracy and its seeming desire to impose that disability on the Nation.  For an excellent book on this subject, see Chris Mooney's "The Republican War on Science."
-- DLF

Handwriting "EXPERTISE"??

This past Saturday, August 19th, the Jacksonville Daily Progress reported the "findings" of a local "handwriting expert" that John M. Karr probably is guilty of the killing of JonBenet Ramsey, based on his analysis of several of Karr's writings and the ransom note left at the scene of the crime.  (Attentive readers will also recall that at least one other handwriting expert had identified the ransom note as having come from the hand of JonBenet's mother.)  According to the story,

Local handwriting expert Don Lehew, of Mt. Selman, has obtained several samples of John M. Karr’s handwriting, as well as, a copy of the Ramsey ransom note, and according to his analysis, they are all written by the same person. Lehew compared the ransom note to an old yearbook entry by Karr and an employment application Karr filled out when applying for a teaching job.
According to Lehew, several writing features on the yearbook entry were identical to the ransom note, including the unusual curvature of Karr’s “D”s and “L”s, and the odd angle of his “S”s.
“In both samples the slant of the writing is mixed; sometimes it slants right, and sometimes it slants left,” Lehew said.

But the story gets better.  This guy, according to the story, can not only identify Karr as the author of the ransom note, but it his expert opinion (based on research, no less) that Karr's writing indicates that he is a pedophile:

“Over the last three years, by collecting samples of known pedophiles, I have created a profile, by identifying the things that are common in their handwriting,” Lehew said. “I’ve looked at writing samples from 23 or 24 known pedophiles to create this profile. I’ve been doing this research for about three years.”
According to Lehew, his profile cannot identify if a person is a pedophile, only that they possess the propensity to be or become one.
“I can’t look at someone’s handwriting and say, “That’s a pedophile.” What I can do is look at it and say, of all the handwriting samples that I have looked at, about 10,000 of them in the past 25 years, this one closely approximates and relates to the handwriting of known pedophiles.”
Based on Lehew’s pedophile profile, Karr’s writing style displays several of the hallmarks of a child molester.
“Triangles or figure eights in the lower zone, retracing, leading in from below the baseline, these are all behaviors that have been observed in convicted pedophiles,” Lehew said. “He (Karr) has the tendency — he scored high on the pedophile chart.”

And Lehew is not just some self-styled expert.  According to the story, he is a member of the American Board of Forensic Examiners and teaches questioned document courses at Handwriting University.  He has also appeared numerous times in both state and federal court and is "certified by the Department of Public Safety to teach questioned document examination to law enforcement throughout Texas."

I could add an editorial comment here, but it hardly seems worth the effort.  I will simply refer readers back to Donald Kennedy's Science editorial (see August 19th post), in which he asked whether "Forensic Science is an Oxymoron."  The answer, clearly, is sometimes yes!
-- DLF

Fame, the Founding Fathers, and Modern Psychology

The New York Times has an interesting article on "the fame motive," in its Science Times section today.  [see full article]  The article observes that psychologists have recently begun to study fame's motivating forces and how some people can be overwhelmingly devoted to its attainment:

For most of its existence, the field of psychology has ignored fame as a primary motivator of human behavior: it was considered too shallow, too culturally variable, too often mingled with other motives to be taken seriously. But in recent years, a small number of social scientists have begun to study and think about fame in a different way, ranking it with other goals, measuring its psychological effects, characterizing its devoted seekers.

The article reminded me of the debate between Anti-federalists and Federalists at the founding of our Republic.  The Federalists, men like James Madison and Alexander Hamilton, who advocated ratification of the Constitution and a strong central government, recognized man's "love of fame," an insight associated with David Hume.  For the Federalists, this love of fame would motivate men to participate in government, but had to be checked and balanced, since it could lead men to abuse the power they held.  One prominent Federalist, John Stevens, for example, criticized the Anti-Federalists' "talk of virtue as the spring of action."  He considered such a basis for government "too feeble."  He said that human nature was self-interested and motivated by ambition:

Can any man, who has a tolerable acquaintance of human nature, imagine that men would so eagerly engage in public affairs, from whence they can hope to derive no personal emolument, merely from the impulse of so exalted, so pure, so disinterested a passion as patriotism, or political virtue?  No!  It is ambition that constitutes the very life and soul of Republican Government.  As fear and attachment insure obedience to Government, so does ambition set its wheels in motion.

Madison, who shared Stevens' views, observed that "Respect for character is always diminished in proportion to the number among whom the blame or praise is to be divided.  Conscience, the only remaining tie, is known to be inadequate in individuals: In large numbrs little is to be expected from it."    Madison's observations of psychology led him to support a government structured by checks and balances, one that would not invest too much authority in any one department.  In The Federalist, No. 51, Madison penned these famous words:

But what is government itself, but the greatest reflection on human nature?  If men were angels, no government would be necessary.  If angels were to govern men, neither external nor internal controls on government would be necessary.  In framing a government which is to be administered by men over men, the great difficulty lies in this: you must first enable the government to control the governed; and in the next place oblige it to control itself.

The Federalist vision of human nature, of course, prevailed.  (I should point out, just to be clear, that the "Federalists" of the founding generation had little in common with the "Federalist Society" of today.  The latter advocate positions that are more closely associated with the Anti-Federalists.)  We tend to forget, however, how much of the behavioral observations of the founders influenced the form of government they established.  Morevover, many of the debates about human nature should continue to inform how we understand and interpret the relations between the branches of the federal government and the dynamic between that government and the states.  Modern psychology is unlikely to definitively answer such basic and profound questions, but modern research methods can help shed light on these ancient debates.  And, perhaps, some of this scientific work might even be relevant to concrete questions we have today, such as how much power should be invested in the Executive Branch in these treacherous times that we live in.  For Madison and many of the other founders, the answer was clear.  In Hamilton's words:

Political writers have established it as a maxim, that, in contriving any system of government, and fixing the several checks and controls of the constitution, every man ought to be supposed a knave; and to have no other end in all his action, but private interest.  By this interest, we must govern him, and by means of it, make him co-operate to public good, notwithstanding his insatiable avarice and ambition.

Hence, while we must invest great power in our elected representatives, we should never forget the basic motivating forces of human nature.  Perhaps the most basic operating principle of the American Constitution is that it checks ambition with ambition through the checks and balances inherent in the division of power.  As the founders understood, Investing too much authority in any one branch, no matter how virtuous we might consider those occupying the offices of that branch, is contrary to the original plan of government and likely to result in the abuse of power.
-- DLF

Fact-finding in Constitutional Cases

On November 8, 2006, the United States Supreme Court will hear argument in the case of Carhart v. Gonzales, the so-called "partial birth abortion" case.  Although the subject matter of the case concerns a highly contentious issue, the legal issue presented should be somewhat less controversial.  Indeed, the underlying matter presented is a subject of disputed scientific opinion.  In short, the basic scientific issue concerns whether a health exception is necessary to a ban on partial birth abortions.  In the challenged law, Congress explicitly found, based on its assessment of the science (after extensive hearings), that a health exception was not necessary.  The question for the Court to decide this term is whether federal courts owe deference to such congressional findings of scientific fact. [The Question Presented can be found here: Download QuestPresSCT.pdf ].

The Justice Department's brief argues that courts owe Congress deference under these circumstances, despite the fact that the resolution of the issue impacts a basic constitutional right.  Indeed, the Justice Department asserts the following remarkable proposition: “[t]here is . . . no principled basis for holding that the degree of deference owed to congressional findings depends on the level of scrutiny applicable to the right at issue.”  In effect, then, Congress (and presumably any State legislature) could revisit constitutional precedents and reconsider the factual premises for those decisions.  Under the government's reasoning, the courts would owe deference to Congressional "findings" that segregation does not negatively impact black schoolchildren (overturning Brown v. Board of Education), or that viability occurs in the sixteenth week of a pregnancy (overturning Roe v. Wade).  The government's position is astounding and wrong.  Among many briefs submitted to the Court demonstrating why this is so, see Download SupremeCourtFINAL.pdf (page numbers may vary from the brief filed, because of formatting differences).
-- DLF

The Ethics of Scientific Evidence

Blog 702 (here), an excellent resource on all things Daubert, offers this quote from Judge Kessler's opinion in United States v. Philip Morris USA, Inc.:

Finally, a word must be said about the role of lawyers in this fifty-year history of deceiving smokers, potential smokers, and the American public about the hazards of smoking and second hand smoke, and the addictiveness of nicotine. At every stage, lawyers played an absolutely central role in the creation and perpetuation of the Enterprise and the implementation of its fraudulent schemes. They devised and coordinated both national and international strategy; they directed scientists as to what research they should and should not undertake; they vetted scientific research papers and reports as well as public relations materials to ensure that the interests of the Enterprise would be protected; they identified “friendly” scientific witnesses, subsidized them with grants from the Center for Tobacco Research and the Center for Indoor Air Research, paid them enormous fees, and often hid the relationship between those witnesses and the industry; and they devised and carried out document destruction policies and took shelter behind baseless assertions of the attorney client privilege.

What a sad and disquieting chapter in the history of an honorable and often courageous profession.

For more, and a copy of the opinion, see here.
-- DLF

Lawyers/Judges Should Read Science

Possibly the biggest impediment to lawyers' and judges' use of scientific research is their general lack of training in the subjects of statistics and research methods.  Short of returning to graduate school for courses in these subjects, it would serve legal professionals well to read books and articles written by scientists.  But any suggested reading list, I think, should go well beyond the specific topic of science and law.  To truly appreciate the way scientists approach the empirical world, we should all be reading general science that is written for a lay audience.  There are, of course, many science writers well worth the time and effort, including such notables as Steven Pinker (see example), Edward O. Wilson (see example), Antonio Damasio (see example), Carl Sagan (see example), and  Stephen Jay Gould (see example).   Along these lines, I would also suggest that legal professionals consider reading Science Magazine, a resource that offers insights into the world of scientists and which regularly contains articles of pressing importance to law and society.  Indeed, Dr. Donald Kennedy, Science's editor, has devoted considerable attention to the question of the law and science connection.  His editorial on forensic science from a couple of years back was a valuable contribution to the debate over the current condition of, and future prospects for, forensic science (see here).
-- DLF

What is the Science and Law Blog?

This Blog is directed at the intersection of science and law.   Its focus concerns the integration of applied scientific research and the substantive law.  It thus is not limited by subject area, on either the law or science side of the ledger.  Topics of interest, therefore, include everything from mass toxic torts to fingerprint identification.  Of course, Daubert and its progeny are very much within the realm of topics of discussion, but this is not a Daubert or Rule 702 Blog.  Several excellent resources on Daubert already exist, including a blog (here), and a tracking service (here).  Instead, this page is organized around the single question of how does, and how should, courts and policy makers use the more or less certain findings (or lack of findings) from science when making decisions.  On the law side, therefore, not only are evidentiary matters of concern, but this question implicates substantive areas of law, including, but not limited to, torts, criminal, administrative, and constitutional. On the science side, subjects of interest will include, but are not limited to, psychology, sociology, political science, economics, toxicology, and epidemiology.

I hope the discussion and postings here will be of interest to both lawyers and scientists.  Indeed, the blog will be organized around this hope.  Increasingly, the two communities of professionals are recognizing the need for cooperation and understanding.  Indeed, I think Daubert is largely premised on the principle that lawyers and judges must know something about the elements of science and hypothesis testing in order to use any claimed insights from the research.  Also, scientists and scientific organizations, have begun to recognize the need to become involved in evaluating and explaining the import and limitations of scientific work.  I hope to create some intellectual bridges between the two communities in order to facilitate their working together more effectively in the future.
-- DLF