Friday, March 24, 2017
Terrific Harvard School of Public Health panel on "Marijuana: The Latest Scientific Findings and Legalization"
Though other commitments prevented me from watching the event live, I am grateful to have been able to find (and find the time) to watch an hour-long panel discussion on marijuana research and reform today as part of The Dr. Lawrence H. and Roberta Cohn Forums as The Harvard T.H. Chan School of Public Health. I watched the full video via this page at The Huffington Post, which provides this "preview":
Twenty-eight states and the nation’s capital allow for the legal use of medical marijuana. The drug is legal for recreational use in eight states and Washington, D.C. But with a new administration in office signaling a crackdown on recreational use, including an attorney general personally opposed to the drug, states are gearing up for a marijuana war.
While medical marijuana has been scientifically proved to ease pain, but the jury is still out on the drug’s other health benefits. A recent study conducted by the National Academies of Sciences, Engineering and Medicine, led by Harvard T.H. Chan School of Public Health professor Marie McCormick, found as much. Ryan Grim, Washington bureau chief for The Huffington Post, will be joined by McCormick and other policy and research experts for a panel discussion on marijuana’s health benefits and legalization.
This page at the Harvard School of Public Health indicates that the video will be posted there soon as well, and it provides this additional summary of the event:
California, Massachusetts, Maine, and Nevada became the latest states to legalize recreational marijuana, bringing to 28 the number of states that have okayed the drug for medicinal use, recreational use, or both. Even more states have rules that allow certain kinds of cannabis extracts to be used for medical purposes. At the same time that state legalization is increasing, the Trump administration is signaling that it may ramp up enforcement of federal drug laws, even when they come into conflict with state laws allowing recreational marijuana use. State and local governments may find themselves on uncertain legal ground. Meanwhile, policymakers navigating this new landscape are also working largely without the benefit of a solid foundation of scientific evidence on the drug’s risks and benefits. In fact, a new National Academy of Medicine report describes notable gaps in scientific data on the short- and long-term health effects of marijuana. What do we know about the health impacts of marijuana, and what do we still need to learn? This Forum brought together researchers studying marijuana’s health impacts with policymakers who are working to implement new laws in ways that will benefit and protect public health.
Thursday, January 12, 2017
National Academies of Sciences, Engineering, and Medicine releases massive new report on "Health Effects of Cannabis and Cannabinoids"
I am very pleased to see that today, just in time for a long weekend, the National Academies of Sciences, Engineering, and Medicine has produced this massive new report titled "The Health Effects of Cannabis and Cannabinoids: The Current State of Evidence and Recommendations for Research." The nearly 400-page report is available for download from this website, and here its the website's brief account of the report's coverage:
In one of the most comprehensive studies of recent research on the health effects of recreational and therapeutic cannabis use, a new report from the National Academies of Sciences, Engineering, and Medicine offers a rigorous review of relevant scientific research published since 1999. This report summarizes the current state of evidence regarding what is known about the health impacts of cannabis and cannabis-derived products, including effects related to therapeutic uses of cannabis and potential health risks related to certain cancers, diseases, mental health disorders, and injuries. Areas in need of additional research and current barriers to conducting cannabis research are also covered in this comprehensive report.
Helpfully, this new Business Insider article provides some of the substantive highlights of this important new report under the headline "11 key findings from one of the most comprehensive reports ever on the health effects of marijuana." Here are excerpts from this press account:
A massive report released today by the National Academies of Sciences, Engineering, and Medicine gives one of the most comprehensive looks — and certainly the most up-to-date — at exactly what we know about the science of cannabis. The committee behind the report, representing top universities around the country, considered more than 10,000 studies for its analysis, from which it was able to draw nearly 100 conclusions.
In large part, the report reveals how much we still have to learn, but it's still surprising to see how much we know about certain health effects of cannabis. This summation was sorely needed, as is more research on the topic.... Before we dive into the findings, there are two quick things to keep in mind.
First, the language in the report is designed to say exactly how much we know — and don't know — about a certain effect. Terms like "conclusive evidence" mean we have enough data to make a firm conclusion; terms like "limited evidence" mean there's still significant uncertainty, even if there are good studies supporting an idea; and different degrees of certainty fall between these levels. For many things, there's still insufficient data to really say anything positive or negative about cannabis.
Second, context is important. Many of these findings are meant as summations of fact, not endorsements or condemnations. For example, the report found evidence that driving while high increased the risk of an accident. But the report also notes that certain studies have found lower crash rates after the introduction of medical cannabis to an area. It's possible that cannabis makes driving more dangerous and that the number of crashes could decrease after introduction if people take proper precautions.
We'll work on providing context to these findings over the next few days but wanted to share some of the initial findings first. With that in mind, here are some of the most striking findings from the report:
• There was conclusive or substantial evidence (the most definitive levels) that cannabis or cannabinoids, found in the marijuana plant, can be an effective treatment for chronic pain, according to the report, which is "by far the most common" reason people request medical marijuana. With similar certainty, they found that cannabis can help treat muscle spasms related to multiple sclerosis and can help prevent or treat nausea and vomiting associated with chemotherapy.
• The authors found evidence that suggested that marijuana increased the risk of a driving crash.
• They also found evidence that in states with legal access to marijuana, children were more likely to accidentally consume cannabis.
We've looked at these numbers before and seen that the overall increases in risk are small — one study found that the rate of overall accidental ingestion among children went from 1.2 per 100,000 two years before legalization to 2.3 per 100,000 two years after legalization. There's still a far higher chance parents call poison control because of kids eating crayons or diaper cream, but it's still important to know that some increased risk could exist.
• Perhaps surprisingly, the authors found moderate evidence (a pretty decent level of certainty and an indication that good data exists) that cannabis was not connected to any increased risk of the lung cancers or head and neck cancers associated with smoking. However, they did find some limited evidence suggesting that chronic or frequent users may have higher rates of a certain type of testicular cancer.
• Connections to heart conditions were less clear. There's insufficient evidence to support or refute the idea that cannabis might increase the risk of a heart attack, though there was some limited evidence that smoking cannabis might be a trigger for a heart attack.
• There was substantial evidence that regular marijuana smokers are more likely to experience chronic bronchitis and that stopping smoking was likely to improve these conditions. There's not enough evidence to say that that cannabis does or doesn't increase the risk for respiratory conditions like asthma.
• There was limited evidence that smoking marijuana could have some anti-inflammatory effects.
• Substantial evidence suggests a link between prenatal cannabis exposure (when a pregnant woman uses marijuana) and lower birth weight, and there was limited evidence suggesting that this use could increase pregnancy complications and increase the risk that a baby would have to spend time in the neonatal intensive care unit.
• In terms of mental health, substantial evidence shows an increased risk of developing schizophrenia among frequent users, something that studies have shown is a particular concern for people at risk for schizophrenia in the first place. There was also moderate evidence that cannabis use is connected to a small increased risk for depression and an increased risk for social anxiety disorder.
• Limited evidence showed a connection between cannabis use and impaired academic achievement, something that has been shown to be especially true for people who begin smoking regularly during adolescence (which has also been shown to increase the risk for problematic use).
• One of the most interesting and perhaps most important conclusions of the report is that far more research on cannabis is needed. Importantly, in most cases, saying cannabis was connected to an increased risk doesn't mean marijuana use caused that risk.
And it's hard to conduct research on marijuana right now. The report says that's largely because of regulatory barriers, including marijuana's Schedule I classification by the Drug Enforcement Administration and the fact that researchers often can't access the same sorts of marijuana that people actually use. Even in states where it's legal to buy marijuana, federal regulations prevent researchers from using that same product.
Without the research, it's hard to say how policymakers should best support legalization efforts — to say how educational programs or mental health institutions should adapt to support any changes, for example. "If I had one wish, it would be that the policymakers really sat down with scientists and mental health practitioners" as they enact any of these new policies, Krista Lisdahl, an associate professor of psychology and director of the Brain Imaging and Neuropsychology Lab at the University of Wisconsin at Milwaukee, told Business Insider in an interview shortly before we could review this report.
It's important to know what works, what doesn't, and what needs to be studied more. This report does a lot to show what we've learned in recent years, but it also shows just how much more we need to learn.
Tuesday, May 24, 2016
"As more states legalize marijuana, adolescents' problems with pot decline: Fewer adolescents also report using marijuana"
The title of this post is the headline of this notable Science Daily release that reports on this notable newly published research in the Journal of the American Academy of Child & Adolescent Psychiatry that surely should be getting lots and lots of attention from marijuana reform advocates. Here are the basics via the Science Daily:
A survey of more than 216,000 adolescents from all 50 states indicates the number of teens with marijuana-related problems is declining. Similarly, the rates of marijuana use by young people are falling despite the fact more U.S. states are legalizing or decriminalizing marijuana use and the number of adults using the drug has increased.
Researchers at Washington University School of Medicine in St. Louis examined data on drug use collected from young people, ages 12 to 17, over a 12-year span. They found that the number of adolescents who had problems related to marijuana -- such as becoming dependent on the drug or having trouble in school and in relationships -- declined by 24 percent from 2002 to 2013.
Over the same period, kids, when asked whether they had used pot in the previous 12 months, reported fewer instances of marijuana use in 2013 than their peers had reported in 2002. In all, the rate fell by 10 percent. Those drops were accompanied by reductions in behavioral problems, including fighting, property crimes and selling drugs. The researchers found that the two trends are connected. As kids became less likely to engage in problem behaviors, they also became less likely to have problems with marijuana.
The study's first author, Richard A. Grucza, PhD, an associate professor of psychiatry, explained that those behavioral problems often are signs of childhood psychiatric disorders. "We were surprised to see substantial declines in marijuana use and abuse," he said. "We don't know how legalization is affecting young marijuana users, but it could be that many kids with behavioral problems are more likely to get treatment earlier in childhood, making them less likely to turn to pot during adolescence. But whatever is happening with these behavioral issues, it seems to be outweighing any effects of marijuana decriminalization."
The new study is published in the June issue of the Journal of the American Academy of Child & Adolescent Psychiatry. The data was gathered as part of a confidential, computerized study called the National Survey on Drug Use and Health. It surveys young people from different racial, ethnic and income groups in all 50 states about their drug use, abuse and dependence.
In 2002, just over 16 percent of those 12 to 17 reported using marijuana during the previous year. That number fell to below 14 percent by 2013. Meanwhile, the percentage of young people with marijuana-use disorders declined from around 4 percent to about 3 percent.
At the same time, the number of kids in the study who reported having serious behavior problems -- such as getting into fights, shoplifting, bringing weapons to school or selling drugs -- also declined over the 12-year study period. "Other research shows that psychiatric disorders earlier in childhood are strong predictors of marijuana use later on," Grucza said. "So it's likely that if these disruptive behaviors are recognized earlier in life, we may be able to deliver therapies that will help prevent marijuana problems -- and possibly problems with alcohol and other drugs, too."
Thursday, August 20, 2015
The title of this post is drawn from the headline of this Newsweek piece from last month that I just came across. Though it seems from this new news article that former President Jimmy Carter may not be getting a chemotherapy-based cancer treatment, this Newsweek article seemed worth spotlighting on a day when a former US Prez is talking about his cancer diagnosis and coming treatments. (In a coming post, I will highlight another newer Newsweek story on marijuana reform that I think merits even more attention.) Here in a notable excerpt from the lengthy chemo piece:
A growing number of cancer patients and oncologists view the drug as a viable alternative for managing chemotherapy’s effects, as well as some of the physical and emotional health consequences of cancer, such as bone pain, anxiety and depression. State legislatures are following suit; medical cannabis is legal in 23 states and the District of Columbia, and more than a dozen other states allow some patients access to certain potency levels of the drug if a physician documents that it’s medically necessary, or if the sick person has exhausted other options. A large number of these patients have cancer, and many who gain access to medical marijuana report that it works.
“A day doesn’t go by where I don’t see a cancer patient who has nausea, vomiting, loss of appetite, pain, depression and insomnia,” says Dr. Donald Abrams, chief of hematology-oncology at San Francisco General Hospital and a professor of clinical medicine at the University of California, San Francisco. Marijuana, he says, “is the only anti-nausea medicine that increases appetite.”
It also helps patients sleep and elevates their mood — no easy feat when someone is facing a life-threatening illness. “I could write six different prescriptions, all of which may interact with each other or the chemotherapy that the patient has been prescribed. Or I could just recommend trying one medicine,” Abrams says.
A 2014 poll conducted by Medscape and WebMD found that more than three-quarters of U.S. physicians think cannabis provides real therapeutic benefits. And those working with cancer patients were the strongest supporters: 82 percent of oncologists agreed that cannabis should be offered as a treatment option.
Dr. Benjamin Kligler, associate professor of family and social medicine at Albert Einstein College of Medicine, says there has been enough research to prove that at a bare minimum cannabis won’t actually harm a person. In addition, “given what we've seen anecdotally in practice I think there's no reason we shouldn't see more integration of cannabis in the long run as a strategy,” he says. “We have this extremely safe, extremely useful medicine that could potentially benefits a huge population.”
Thursday, August 13, 2015
International Centre for Science in Drug Policy releases "State of the Evidence: Cannabis Use and Regulation"
I am very pleased to see that the International Centre for Science in Drug Policy (ICSDP), a group of scientists and academics who seek to "ensure that policy responses to the many problems posed by illicit drugs are informed by the best available scientific evidence," has released this effective and timely new report titled "State of the Evidence: Cannabis Use and Regulation." Here is the report's introduction:
The regulation of recreational cannabis markets has become an increasingly important policy issue in a number of jurisdictions. Colorado and Washington State made headlines in 2012 when they became the first jurisdictions in the world to legalize and regulate the adult use and sale of cannabis for non-medical purposes. In 2013, Uruguay became the first country to legalize and regulate recreational cannabis markets. Momentum towards regulation continued in the United States in 2014 with successful ballot initiatives in Alaska, Oregon, and the District of Columbia. Globally, the issue of cannabis regulation is front and center in a growing number of jurisdictions, including Canada, Jamaica, Italy, Spain, several Latin American countries, and a number of additional U.S. states, including California, set to vote on legalization initiatives in 2016.
Unsurprisingly, given the robust global conversation around the regulation of recreational cannabis markets, claims about the impacts of cannabis use and regulation are increasingly part of the public discourse. Unfortunately, though, these claims are often unsupported by the available scientific evidence. Another reoccurring problem in the public discourse is the selective inclusion of research studies based on their support for a predetermined narrative. The intentional exclusion of studies with contradictory findings does not allow for an objective review and analysis of all the evidence. This “cherry picking” of the evidence is a routine practice that distorts public understanding. By outlining the current state of all the scientific evidence on common cannabis claims, State of the Evidence: Cannabis Use and Regulation strives to ensure that evidence, rather than rhetoric, plays a central role in policymaking around this important issue.
The harms of misrepresenting the scientific evidence on cannabis should not be overlooked. Given that policy decisions are influenced by public opinion and media reports, public discourse needs to be well informed. By addressing knowledge gaps with scientific findings, the ICSDP hopes to dispel myths about cannabis use and regulation, and ensure that the scientific evidence on these topics is accurately represented. Only then can evidence-based policy decisions be made.
Readers of this report will notice three repeating themes emerge through the discussion of the scientific evidence on common cannabis claims.
First, many of the claims confuse correlation and causation. Although scientific evidence may find associations between two events, this does not indicate that one necessarily caused the other. Put simply, correlation does not equal causation. This is a commonly made mistake when interpreting scientific evidence in all fields, and is unsurprisingly a recurring source of confusion in the discourse on cannabis use and regulation.
Second, for several of these claims, the inability to control for a range of variables (“confounders”) means that in many cases, we cannot conclude that a particular outcome was caused by cannabis use or regulation. Unless scientists can remove all other possible explanations, the evidence cannot conclusively say that one specific explanation is true.
Third, many of the claims cannot be made conclusively as there is insufficient evidence to support them. Findings from a single study or a small sample cannot be generalized to entire populations. This is especially pronounced for claims related to cannabis regulation, as not enough time has passed since the regulation of recreational cannabis in Colorado, Washington State, and Uruguay to examine many of the impacts of these policy changes.
These three common pitfalls are important to take into account when reading media reports and advocacy materials that suggest scientists have conclusively made some finding related to cannabis use or regulation. In many cases, due to the reasons outlined above, this will actually result in a misrepresentation of the scientific evidence.
State of the Evidence: Cannabis Use and Regulation is comprised of two sections: Common Claims on Cannabis Use and Common Claims on Cannabis Regulation.
Common Claims on Cannabis Use presents evidence on frequently heard claims about cannabis use, including claims on the addictive potential of cannabis, cannabis as a “gateway” drug, the potency of cannabis, and the impact of cannabis use on the lungs, heart, and brain (in terms of IQ, cognitive functioning, and risk of schizophrenia).
Common Claims on Cannabis Regulation presents evidence on frequently heard claims about the impacts of cannabis regulation, including the impact of regulation on cannabis availability, impaired driving, the use of cannabis, drug crime, drug tourism, and “Big Marijuana.”
For each claim, the relevant available scientific evidence is presented and the strength of the scientific evidence in support of the claim is determined. Readers will notice that none of the claims are strongly supported by the scientific evidence, reinforcing the significant misrepresentation of evidence on cannabis use and regulation.
We hope that the evidence contained in this report meaningfully contributes to the global conversation around cannabis policy and helps policymakers, as well as general readers, separate scientific evidence from conjecture.
Wednesday, August 5, 2015
The title of this post is the headline of this notable Fox News piece reporting on notable new research published by the American Physiological Association. Here are the basic details:
A new study reports that chronic marijuana use in teenage boys does not appear to be linked to later physical or mental health issues such as depression, psychotic symptoms or asthma. The study, published by the American Physiological Association, did not include teenage girls.
Researchers from the University of Pittsburgh Medical Center and Rutgers University compiled data by tracking 408 males from adolescence into their mid-30s. The participants were placed into four groups based on their reported marijuana use: low or non-users, early chronic users, participants who only smoked during adolescence, and those who began using marijuana late in their teens and continued through adulthood. Early chronic users reported higher marijuana use, which increased in their teens to a peak of more than 200 days per year on average when they were 22 years old, the news release said.
The study was an offshoot of the Pittsburg Youth Study, which tracked 14-year-old male students in Pittsburgh public schools in the late 1980s, according to a news release. Participants were surveyed annually or semiannually, and a follow up survey was conducted in 2009-2010 when the volunteers were 36 years old.
Based on the results of prior studies, authors expected to find a link between teen marijuana use and the later development of psychotic symptoms, cancer, asthma or respiratory problems but found none, according to a news release. “What we found was a little surprising,” lead researcher Jordan Bechtold, a psychology research fellow at the University of Pittsburgh Medical Center, said in the release. “There were no differences in any of the mental or physical health outcomes that we measured regardless of the amount of frequency of marijuana used during adolescence.”
Saturday, June 6, 2015
The title of this post is from a sentence in this notable new OZY article, which is headlined "Getting Stoned, Getting Freaky." Here are some (amusing? prurient? silly?) excerpts:
[G]etting intimate while getting high is not exactly a 21st-century invention. Cannabis was used for a range of medicinal purposes more than 10 centuries ago in ancient India, including — you guessed it — as a turn-on trigger. There are at least 18 variations of bhang, a grass-infused drink that was used as a sort of love potion in the ancient Ayurvedic and Unani Tibbi systems of medicine, according to the United Nations Office on Drugs and Crime. Some experts, like anthropologist Christian Rätsch in his book Plants of Love: The History of Aphrodisiacs and a Guide to Their Identification and Use, argue that weed was a central component to the sexual part of ancient Hindu and Buddhist Tantra, though it’s still up for debate how prominently it was featured.
And modern science hasn’t exactly cleared the haze when it comes to pot’s effect on sex. A flurry of studies in the 1980s found mixed results, with some noting that bud put a serious damper on sex while others found it lit a fire under the bed, according to Michael Castleman, a journalist who specializes in sexuality. Research into the weed/sex tie-up went on hiatus until about a decade ago, when Canadian researchers picked up the torch and found that one-third of interviewees used weed specifically for its sex-enhancing properties, while another third said it “seldom” or “never” improved sex. “It doesn’t work the same way for everybody,” warns Andrew Hathaway, one of the study’s authors and an associate professor of sociology at the University of Guelph.
Today, weed can seem like one person’s magical cup of tea and not another’s because it’s not an objective aphrodisiac per se, says Dr. Lester Grinspoon, professor emeritus of psychiatry at Harvard Medical School and one of the most widely known marijuana researchers. Marijuana doesn’t increase libido or sexual performance so much as it enhances the sensations of sex. Just like how food tastes better and music sounds better while stoned, Grinspoon says, “sex feels better.” When he first started smoking in his 40s, it took Grinspoon a few tries to feel anything. It finally struck him that he was high when he got into bed, he says. But nowadays getting stoned is a bit different given how much stronger the drug is. Smoking too much can make someone fold in on themselves or become paranoid, which isn’t exactly the sexiest move.
Science be damned, weed-centric entrepreneurs are seemingly willing to try anything to make money in an industry that many are calling the Wild West. Recent pot legalization in a number of U.S. states — the big vote in California happens during next year’s election — has galvanized some to mix weed and sex to make some money. There’s Foria, a well-received marijuana-infused sex lube for women, and more products are likely to follow. Even some porn stars are cashing in by partnering with growers and having smoke sessions on live cams with fans, says Chauntelle Tibbals, a sociologist who has done extensive research on the adult entertainment industry. Hell, there’s even an ad for a sex columnist “with weed focus.”
There’s obviously a lot more at stake here than making money. Pro-weed activists promote weed as an immaculate aphrodisiac that can help deter date rape, since alcohol tends to lead to aggression while pot tends to have the opposite effect. But critics warn the drug’s strength will lead to unsafe sex. The reality, says Tyler Osterhaus, an anti-violence educator who has worked for the Colorado Department of Public Health and Environment’s Sexual Violence Prevention Program, is somewhere in the middle. He adds, however, that weed can certainly lower someone’s guard and make them vulnerable to sexual violence.
Sunday, May 17, 2015
In this post from a few weeks ago, I was promped by an article about the Tesla battery and marijuana cultivation to ask this question is a post title: "Could/will the marijuana industry become a boon for green energy innovation?". Continuing with the theme of innovations for ganja growing is this fascinating new article via the International Business Times headlined "Legal Marijuana Cultivation Is Driving A Technology 'Revolution' In Industrial Agriculture." Here are excerpts:
[A] growing number of companies in North America [are] designing new products and systems specifically for the cultivation of cannabis, a finicky crop that needs a precise balance of light, moisture and water to thrive. Although these cannabis ventures aren’t exactly reinventing the wheel -- greenhouse technologies have existed for decades -- they are injecting the kinds of capital and brainpower into the field of industrial agriculture that simply wasn’t there a decade ago.
They’re also adding a new level of urgency. As more countries and U.S. states soften their policies on both medical and recreational marijuana, companies are racing to become the industry leaders in data-mining software, ultraefficient lamps and water-sipping irrigation systems. These tools will benefit more than marijuana growers alone: Industrial food producers and tree growers could adapt the same technologies to cut energy costs and boost their crops. Operators of large buildings could use the systems to lower their electricity use.
“Cannabis is spurring on an ag-tech revolution,” said Troy Dayton, CEO of ArcView Group, a cannabis-industry research firm in Oakland, California. “This is a boom born entirely out of ending repressive laws. The market is already there, it’s just moving from the shadows into the light. That’s why you’re seeing this incredible growth and why so many people see it as a once-in-a-lifetime [business] opportunity.”
That market is rapidly expanding in the U.S., where 23 states have already legalized medical marijuana, and three states -- Alaska, Colorado and Washington -- allow recreational-marijuana sales. Voters in Oregon approved a ballot measure last fall that allows for personal pot use and limited cultivation. The policy takes effect July 1. In Texas, Ohio, Nebraska and a number of other states, voters and policymakers are considering similar initiatives. (In Canada, medical-marijuana use was legalized in 2001, and recent policy changes are enabling a rise in industrial growing operations.)....
Companies such as Heliostat are moving into the cannabis space for three key reasons -- first and foremost, cash. Unlike tomato and pepper producers, cannabis growers boast wide profit margins, giving them a bigger budget for top-of-the-line technologies and a greater appetite for research and experimentation....
Second, young technology whizzes and expert plant biologists are both bringing their skills to the burgeoning sector. “For the newer generation that’s just getting out of college or new to the workplace, cannabis is a more interesting project than say a real-estate project, or a lettuce project,” said Michael Mayes, CEO of Quantum 9 Inc., a Chicago consulting firm for cannabis cultivation and manufacturing. “The cool factor can drive innovation.”
Third, there is plenty of demand among growers. As they build new greenhouses and indoor facilities, they’re interested in shaving off as much electricity and water consumption as possible to reduce operating expenses and protect profit margins as more players enter the market.
Dayton of ArcView Group said the cannabis industry is still in the earliest stages of its technology “renaissance,” and that the only thing holding it back are prohibitive marijuana policies in certain states.
Even so, the gradual easing of cannabis laws is already drawing interest from mainstream businesses, including a subsidiary of Scotts Miracle-Gro Co. The company’s Hawthorne Gardening Co. in April purchased General Hydroponics Inc. and Bio-Organic Solutions Inc., which make liquid nutrients for indoor marijuana cultivation. Terms were not disclosed, but the acquisition should make Scotts, with its $2.97 billion in annual revenue, a formidable player in the marijuana market.
Prior related post:
Tuesday, February 17, 2015
Under a Science-Based Jurisprudence of Dangerousness "[rest of title]
The relationship between new medical and recreational marijuana laws and "drugged driving" is a hot and vexing one. Doug has previously posted an article discussing this topic; this article by Andrea L. Roth available via SSRN examines and rejects the analogy between drunk driving and drugged driving by looking at the history of drunk driving laws specifically their scientific underpinning. .
Here's the abstract:
As the marijuana legalization movement lurches forward, states face a jurisprudential dilemma in addressing the burgeoning public health issue of “drugged driving.” Zero-tolerance laws targeting driving with any illegal drug in one’s system, justified under a “jurisprudence of prohibition” based on the blameworthiness of the drug itself, are no longer a good fit. Instead, states have attempted to treat marijuana like alcohol, and have imported drunk driving’s “jurisprudence of dangerousness,” by enacting “per se” driving-under-the-influence-of (DUI)marijuana laws redefining DUI as driving with a certain amount of THC, marijuana’s main psychoactive compound, in one’s blood. These laws are legitimate, we are told, because they are analogous to “per se” .08% blood-alcohol concentration (BAC) impairment laws. What lawmakers have forgotten, and what legal scholars have largely neglected, is the buried and colorful history of drunk driving’s jurisprudence of dangerousness, and the scientific framework established by the country’s first “traffic czar,” William Haddon Jr., for proving the link between specific BACs and crash risk. Under this framework – which focuses first and foremost on fatal single-car crashes and case-control studies with a randomly selected control group – the illegitimacy of the new wave of DUI marijuana laws is painfully obvious. In fact, the few single-car crash and case-control studies that have been conducted have found no relationship between THC blood levels and increased relative risk of crash. Properly understood, the history of drunk driving offers what is still the only valid scientific framework for using the criminal law as an instrument of public safety.
Thursday, February 12, 2015
Shouldn't latest health research prompt pot prohibitionists to advocate more for tobacco restrictions?
The question in the title of this post is prompted by this new AP report headlined "Study ties more deaths, types of disease, to smoking." Here are excerpts:
Breast cancer, prostate cancer, and even routine infections. A new report ties these and other maladies to smoking and says an additional 60,000 to 120,000 deaths each year in the United States are probably due to tobacco use.
The study by the American Cancer Society and several universities, published in Thursday's New England Journal of Medicine, looks beyond lung cancer, heart disease and other conditions already tied to smoking, and the 480,000 U.S. deaths attributed to them each year.
"Smokers die, on average, more than a decade before nonsmokers," and in the U.S., smoking accounts for one of every five deaths, Dr. Graham Colditz, an epidemiologist at Washington University School of Medicine in St. Louis wrote in a commentary in the journal. The report shows that current estimates "have substantially underestimated the burden of smoking on society," he wrote. About 18 percent of U.S. adults smoke....
Researchers looked at nearly 1 million Americans 55 and older taking part in five studies, including the National Institutes of Health-AARP Diet and Health Study, since 2000. They tracked the participants' health for about 10 years and compared deaths from various causes among smokers, never smokers and former smokers, taking into account other things that can influence risk such as alcohol use.
Death rates were two to three times higher among current smokers than among people who never smoked. Most of the excess deaths in smokers were due to 21 diseases already tied to smoking, including 12 types of cancer, heart disease and stroke. But researchers also saw death rates in smokers were twice as high from other conditions such as kidney failure, infections, liver cirrhosis and some respiratory diseases not previously tied to smoking.
A few prior related posts:
Sunday, August 3, 2014
In this recent post, I highlighted to potent work done by folks at the Washington Post concerning marijuana research and data in this detailed Wonkblog piece highlighting all the problems with all the science claims by the federal government to justify marijuana prohibition. I now just saw this notable follow-up piece by Christopher Ingraham at Wonkblog headlined "The federal government’s own statistics show that marijuana is safer than alcohol." Here are excerpts:
Opponents of marijuana legalization return to one particular number over and over in their arguments: the number of emergency room visits involving marijuana. [An] ONDCP fact sheet breathlessly reports that "mentions of marijuana use in emergency room visits have risen 176 percent since 1994, surpassing those of heroin." The Drug Enforcement Administration's "Dangers and Consequences of Marijuana Abuse," a 41-page tour-de-force of decontextualized factoids, reports that marijuana was involved in nearly half a million E.R. visits in 2011, second only to cocaine.
The problem, of course, is that these numbers are meaningless without knowing how many people are using those drugs to start with. When you consider that there are approximately 70 times more marijuana users than heroin users in the United States, it makes sense that more of the former are going to the hospital than the latter.
Since the government doesn't provide these comparisons in a meaningful way, I've done it myself....
For 2010, the latest year for which complete alcohol data are available, I grabbed the number of regular users from the National Survey on Drug Use and Health. "Regular," in this case, means people who report using a given substance in the past month. I then grabbed 2010 E.R. visits involving these substances from the Drug Abuse Warning Network. This is a hospital reporting system that collects detailed data on all E.R. admissions involving a given drug. These E.R. visits can involve the use of multiple substances, so the numbers for each drug involve all visits for which that drug was listed as a contributing factor....
The figures clearly show that on a per-user basis, marijuana is considerably less likely to send you to the E.R. than heroin, cocaine or meth. Marijuana users are also 75 percent less likely to face an E.R. visit than prescription drug abusers.
But most surprisingly, marijuana is significantly safer to use than alcohol. For every thousand regular alcohol drinkers there are eight more trips to the E.R. than for every thousand marijuana users. Or in other words, alcohol is about 30 percent more likely to send you to the E.R. than marijuana.
These are all the federal government's own numbers, and they show that marijuana is considerably less harmful to users than alcohol. At the risk of sounding like a broken record, this comports with just about every other credible study of the drug.
Thursday, July 31, 2014
The title of this post is drawn in part from the headline of this latest editorial in the New York Times series explaining its editorial judgment that marijuana prohibition should be ended (first noted here). Here is an excerpt from this editorial:
As with other recreational substances, marijuana’s health effects depend on the frequency of use, the potency and amount of marijuana consumed, and the age of the consumer. Casual use by adults poses little or no risk for healthy people. Its effects are mostly euphoric and mild, whereas alcohol turns some drinkers into barroom brawlers, domestic abusers or maniacs behind the wheel.
An independent scientific committee in Britain compared 20 drugs in 2010 for the harms they caused to individual users and to society as a whole through crime, family breakdown, absenteeism, and other social ills. Adding up all the damage, the panel estimated that alcohol was the most harmful drug, followed by heroin and crack cocaine. Marijuana ranked eighth, having slightly more than one-fourth the harm of alcohol.
Federal scientists say that the damage caused by alcohol and tobacco is higher because they are legally available; if marijuana were legally and easily obtainable, they say, the number of people suffering harm would rise. However, a 1995 study for the World Health Organization concluded that even if usage of marijuana increased to the levels of alcohol and tobacco, it would be unlikely to produce public health effects approaching those of alcohol and tobacco in Western societies.
Most of the risks of marijuana use are “small to moderate in size,” the study said. “In aggregate, they are unlikely to produce public health problems comparable in scale to those currently produced by alcohol and tobacco.”
While tobacco causes cancer, and alcohol abuse can lead to cirrhosis, no clear causal connection between marijuana and a deadly disease has been made. Experts at the National Institute on Drug Abuse, the scientific arm of the federal anti-drug campaign, published a review of the adverse health effects of marijuana in June that pointed to a few disease risks but was remarkably frank in acknowledging widespread uncertainties. Though the authors believed that legalization would expose more people to health hazards, they said the link to lung cancer is “unclear,” and that it is lower than the risk of smoking tobacco....
The American Society of Addiction Medicine, the largest association of physicians specializing in addiction, issued a white paper in 2012 opposing legalization because “marijuana is not a safe and harmless substance” and marijuana addiction “is a significant health problem.”
Nonetheless, that health problem is far less significant than for other substances, legal and illegal. The Institute of Medicine, the health arm of the National Academy of Sciences, said in a 1999 study that 32 percent of tobacco users become dependent, as do 23 percent of heroin users, 17 percent of cocaine users, and 15 percent of alcohol drinkers. But only 9 percent of marijuana users develop a dependence. “Although few marijuana users develop dependence, some do,” according to the study. “But they appear to be less likely to do so than users of other drugs (including alcohol and nicotine), and marijuana dependence appears to be less severe than dependence on other drugs.”
There’s no need to ban a substance that has less than a third of the addictive potential of cigarettes, but state governments can discourage heavy use through taxes and education campaigns and help provide treatment for those who wish to quit.
One of the favorite arguments of legalization opponents is that marijuana is the pathway to more dangerous drugs. But a wide variety of researchers have found no causal factor pushing users up the ladder of harm. While 111 million Americans have tried marijuana, only a third of that number have tried cocaine, and only 4 percent heroin. People who try marijuana are more likely than the general population to try other drugs, but that doesn’t mean marijuana prompted them to do so.
Marijuana “does not appear to be a gateway drug to the extent that it is the cause or even that it is the most significant predictor of serious drug abuse,” the Institute of Medicine study said. The real gateway drugs are tobacco and alcohol, which young people turn to first before trying marijuana.
This NY Times piece is a potent and effective review about what we really know about marijuana's health and societal impact. Even more powerful on the same front, though, is this remarkable new Wonkblog piece from the Washington Post that highlights all the problems with all the science claims by the federal government to justify marijuana prohibition. The title of this piece, with is a must-read for anyone who really care about both the science and advocacy realities surrounding marijuana reform, is "The federal government’s incredibly poor, misleading argument for marijuana prohibition." Here is how it gets started:
The New York Times editorial board is making news with a week-long series advocating for the full legalization of marijuana in the United States. In response, the White House's Office of National Drug Control Policy (ONDCP) published a blog post Monday purporting to lay out the federal government's case against marijuana reform.
That case, as it turns out, it surprisingly weak. It's built on half-truths and radically decontextualized facts, curated from social science research that is otherwise quite solid. I've gone through the ONDCP's arguments, and the research behind them, below.
The irony here is that with the coming wave of deregulation and legalization, we really do need a sane national discussion of the costs and benefits of widespread marijuana use. But the ONDCP's ideological insistence on prohibition prevents them from taking part in that conversation.
July 31, 2014 in Assembled readings on specific topics, Federal Marijuana Laws, Policies and Practices, Medical Marijuana Data and Research, Recreational Marijuana Data and Research, Science | Permalink | Comments (0)
Wednesday, June 11, 2014
The title of this post is the title of this notable new report from the Drug Policy Alliance. Here is an excerpt from the report's executive summary:
The Drug Enforcement Administration (DEA) is charged with enforcing federal drug laws. Under the Controlled Substances Act of 1970, its powers include the authority to schedule drugs (alongside other federal agencies) and to license facilities for the production and use of scheduled drugs in federally-approved research. Those powers are circumscribed by a statute that requires the agency to make its determinations based on scientific data.
The case studies compiled in this report illustrate a decades-long pattern of behavior that demonstrates the agency's inability to exercise its responsibilities in a fair and impartial manner or to act in accord with the scientific evidence – often as determined by its Administrative Law Judges.
The following case studies are included in this report:
- DEA Obstructs Marijuana Rescheduling: Part One, 1973-1994
- DEA Overrules Administrative Law Judge to Classify MDMA as Schedule I, 1985
- DEA Obstructs Marijuana Rescheduling: Part Two, 1995-2001
- DEA Overrules Administrative Law Judge to Protect Federal Monopoly on Marijuana for Research, 2001-2013
- DEA Obstructs Marijuana Rescheduling: Part Three, 2002-2013
These case studies reveal a number of DEA practices that work to maintain the existing, scientifically unsupported drug scheduling system and to obstruct research that might alter current drug schedules.
Tuesday, April 29, 2014
This is your brain on drugs: what a recent fMRI study can and can’t tell us about the effects of marijuana use
Two weeks ago (okay, I'm late to the party), news broke of a new study showing that the brains of casual marijuana users are different than those of non-users. The study was just published in the Journal of Neuroscience and can be found here.
The researchers used magnetic resonance imaging (MRI) to scan the brains of 40 young adults aged 18-25. 20 of those subjects were casual marijuana users and 20 were non-users. Controlling for other behaviors such as alcohol and tobacco use, the researchers found that marijuana use was correlated with changes to the shape, size, and density of particular areas of the brain. From the study:
“The results of this study indicate that in young, recreational marijuana users, structural abnormalities in gray matter density, volume, and shape of the nucleus accumbens and amygdala can be observed. Pending confirmation in other cohorts of marijuana users, the present findings suggest that further study of marijuana effects are needed to help inform discussion about the legalization of marijuana.”
The study generated a lot of media coverage, and, unfortunately, over-statements of the study’s actual implications for ongoing policy debates. For example, the Society for Neuroscience issued a press release for the study. The release, while titled with appropriate caution (“Brain Changes are Associated with Casual Marijuana Use in Young Adults”), relays unsupported claims from scientists regarding the ramifications of the study. One of the authors, Hans Breiter, is quoted as saying ““This study raises a strong challenge to the idea that casual marijuana use isn’t associated with bad consequences.” And Carl Lupica, a researcher from the National Institute on Drug Abuse who was not involved with the study, similarly suggests that “This study suggests that even light to moderate recreational marijuana use can cause changes in brain anatomy.”
The problem is that the study doesn’t necessarily support such conclusions. The study’s findings, while intriguing and valuable, are still quite limited. For one thing, the study will need to be replicated. The subject pool of 40 is rather small. That’s not reason enough to dismiss the study -- much brain science research relies on small n studies, because MRIs are cumbersome and expensive, and one can find statistically significant results with small pools – but it is reason to be particularly cautious about the results pre-replication.
Second, correlation doesn’t equal causation. Law policymakers commonly ignore this important scientific concept, but even scientists sometimes get ahead of themselves and jump to conclusions not warranted by a study’s design. In this study, for example, it is quite possible that people who use marijuana have differently sized and shaped brains to begin with; for example, maybe their brains are simply wired to seek out more risky behaviors and that’s why they’ve decided to use an illicit substance. Since we don’t know the size and shapes of these brains before they started using marijuana, we can’t say which came first: the marijuana usage or “the structural abnormalities in gray matter density, volume, and shape of the nucleus accumbens and amygdala.”
Third, even if the study’s results could be replicated and even if they could (somehow) demonstrate a causal connection between marijuana use and brain structure, it’s not clear from this study anyway why we should care. To be sure, different areas of the brain are associated with different functions and I wouldn't want to tinker with the size, shape, or density of my brain. But the study’s author’s can’t yet say that the changes they observe in brain structure necessarily cause negative changes in behavior. For example, some studies suggest that the nucleus accumbens might play a role in drug addiction. But it’s not clear whether that changes observed in this study are associated with (let alone cause) marijuana addiction or any other bad behavioral outcomes; indeed, the authors made a point of excluding “dependent” marijuana users from the subject pool.
Law and neuroscience is a very promising field. It is generating intriguing findings concerning important issues like culpability. But as the best in this nascent field know, there is still much to be learned about the brain. This study is an intriguing development and clearly worthy of more follow ups. I think research on the brain cold help us understand marijuana’s effects and put them in perspective with those of alcohol, tobacco, cocaine, etc. But for now, bold statements about the import of brain science for policy debates over marijuana seem premature.
April 29, 2014 in Criminal justice developments and reforms, Current Affairs, Medical Marijuana Commentary and Debate, Medical Marijuana Data and Research, Medical Marijuana State Laws and Reforms, Recreational Marijuana Commentary and Debate, Recreational Marijuana Data and Research, Recreational Marijuana State Laws and Reforms, Science | Permalink | Comments (2)
Thursday, March 6, 2014
As reported in this lengthy local article, headlined "Conservative committee opens door to medical marijuana for Florida," a notable swing/southern state now has a number of notable legislators talking in notable ways about marijuana reform. Here are excerpts:
One conservative Republican who has suffered from brain cancer talked about the deceit of the federal government in hiding the health benefits of marijuana for his cancer. Another legislator reluctantly met with a South Florida family, only to be persuaded to support legalizing the drug.
Then there was Rep. Charles Van Zant, the surly Republican from Palatka who is considered the most conservative in the House. He not only voted with his colleagues Wednesday to pass out the bill to legalize a strain of marijuana for medical purposes, he filed the amendment to raise the amount of psychoactive ingredients allowed by law — to make it more likely the drug will be effective.
The 11-1 vote by the House Subcommittee on Criminal Justice, was a historic moment for the conservatives in the GOP-dominated House. It was the first time in modern history that the Florida Legislature voted to approve any marijuana-related product. “That’s because people here in Tallahassee have realized that we can’t just have a bumper-sticker approach to marijuana where you’re either for it or against it,” said Rep. Matt Gaetz, R-Shalimar, the committee chairman and sponsor of the bill after the emotional hearing. “Not all marijuana is created equally.”
The committee embraced the proposal, HB 843, by Gaetz and Rep. Katie Edwards, D-Plantation, after hearing heart-wrenching testimony from families whose children suffer from chronic epilepsy. A similar bill is awaiting a hearing in the Senate, where Senate president Don Gaetz, a Niceville Republican and Matt’s father, has said he has heard the testimony from the families and he wants the bill to pass as a first step. “Here I am, a conservative Republican but I have to try to be humble about my dogma,” Senate President Don Gaetz told the Herald/Times....
For a committee known for its dense, often tedious scrutiny of legal text, the debate was remarkable. Rep. Dave Hood, a Republican trial lawyer from Daytona Beach who has been diagnosed with brain cancer, talked about how the federal government knew in 1975 of the health benefits of cannabis in stopping the growth of “brain cancer, of lung cancer, glaucoma and 17 diseases including Lou Gehrig’s disease” but continued to ban the substance. “Frankly, we need to be a state where guys like me, who are cancer victims, aren’t criminals in seeking treatment I’m entitled too,” Hood said.
Rep. Dane Eagle, R-Cape Coral, said he had his mind made up in opposition to the bill, then changed his mind after meeting the Hyman family of Weston. Their daughter, Rebecca, suffers from Dravet’s Syndrome. “We’ve got a plant here on God’s green earth that’s got a stigma to it — but it’s got a medical value,” Eagle said, “I don’t want to look into their eyes and say I’m sorry we can’t help you,” he said. “We need to put the politics aside today and help these families in need.”
The Florida Sheriff’s Association, which adamantly opposes a constitutional amendment to legalize marijuana for medical use in Florida, surprised many when it chose not to speak up. Its lobbyist simply announced the group was “in support.” The bi-partisan support for the bill was summed up by Rep. Dave Kerner, a Democrat and lawyer from Lake Worth. “We sit here, we put words on a piece of paper and they become law,” he said. “It’s very rare as a legislator that we have an opportunity with our words to save a life.”
The only opposing vote came from Rep. Gayle Harrell, R-Stuart, an advocate for the Florida Medical Association. Her husband is a doctor. She looked at the families in the audience and, as tears welled in her eyes, she told them: “I can’t imagine how desperate you must be and I want to solve this problem for you.” But, she said the bill had “serious problems.” It allowed for a drug to be dispensed without clinical trials and absent the kind of research that is needed to protect patients from harm. “I really think we need to address this using science,” Harrell said, suggesting legislators should launch a pilot program to study and test the effectiveness of the marijuana strain. “This bill takes a step in the right direction … but it’s not quite there.”
Cross-posted at Marijuana Law, Policy and Reform
Tuesday, February 11, 2014
I've always thought one of the strangest things about the DEA's insistence that marijuana has no currently accepted medical use is that one of the claimed medical uses is as an appetite stimulant. When I cover CSA scheduling of marijuana in my Controlled Substances class, I sometimes joke about whether we really need scientific studies to know that marijuana can make people hungry.
The DEA's position, of course, is that there isn't enough evidence to say that marijuana can stimulate the appetites of cancer and AIDS patients. (The synthetic-THC drug Marinol, on the other hand, has been officially determined to make people hungry.)
Though I don't think it will be enough to satisfy the DEA, today brings some new scientific evidence of (and explanation for) marijuana's effect as an appetite stimulant. The blog Toke of the Town reports:
In a new study published this week in Nature Neuroscience, European researchers claim to have proven that smoking weed does, in fact, give you the munchies. Beyond that, they appear to have isolated the specific region of the brain that is affected by THC consumption, and identified the process through which that desire to eat an entire box of Lucky Charms at 2am comes from.
Thursday, November 14, 2013
The title of this post is the headline of this notable story via UPI. Here are excerpts:
Some medical marijuana enthusiasts in Colorado are taking the "holistic approach" by giving their pets pot to deal with pain.
As animals age, it’s harder for them to do things like fetch, run and play, prompting some owners to prescribe marijuana to help fix the problem. "Arthritis is the really big thing for our pets as they get older, for being able to move about and get their exercise,” pet owner Barbara Novey told local Fox affiliate KXRM.
"So medication of any type that will help someone that is natural will help their pet as well, and I think that maybe our pets can help us purge this reefer madness mentality and realize that it's not the dangerous drug that you think it is."
Novey thinks pot is therapeutic for her pooch, but NorthWest Animal Hospital veterinarian Dr. John Sudduth asserts that giving a dog medical marijuana can be deadly. "There just hasn't been enough research that has been presented to the medical community that would inform us to how to safely use medication such as marijuana. You're really playing with fire. You don't really know what you're giving and what kind of side effects it could have. It could result in serious illness and it could result in death in some cases."
"Pets are not necessarily people in fur coats," Sudduth added. "And how they metabolize medications and utilize medications those are all separate issues that have to be determined."
It is still illegal for veterinarians to prescribe medical marijuana pills. "We need to know about the indications, the usage, the side effects the toxicities and all of those things would have to be worked out before any of these medications, like marijuana might be used," Sudduth said.
Thursday, August 22, 2013
What are the best statistics and strongest research/arguments to support marijuana prohibition and strict criminal enforcement? (Now updated with some...)
I posed the question in the title of this post toward the end of my first class session of the exciting new seminar I am teaching this Fall 2013 semester at OSU's Moritz College of Law. Indeed, I challenged the terrific (and seemingly very insightful and knowledgeable) students taking the seminar to spend the next week looking for (and sending to me for posting here) the very best statistics and the strongest research and arguments they could find to support marijuana prohibition.
Helpfully, and to provide a running start on a question that I hope will generate some dialogue in the comments, there are more than a few anti-drug advocacy groups which have already marshalled materials in support of prohibition. A research assistant helped me assemble links to these notable advocacy groups:
I am hoping that seminar students and other readers might help me cull through the materials on these sites and elsewhere to help provide a sophisticated and detailed answer to the question in the title of this post.
UPDATE: So far, three students from my seminar have sent me a bunch of materials and links concerning what they perceive to be the "best" ideas and arguments to support marijuana prohibition. Here are a few highlights from these efforts:
The DEA in 2010 produced this impressive 81-page booket, titled Speaking Out Against Drug Legalization, which says it is "designed to cut through the current fog of misinformation with hard facts [by] present[ing] an accurate picture of America’s experience with drug use, the nature of the drug problem, and the potential for damage if the United States adopts a more permissive policy on drug abuse." Here are a few (of dozens) of the bullet points from this document discussing the health risks posed by marijuana:
- Harvard University researchers report that the risk of heart attack is five times higher than usual in the hour after smoking marijuana.
- The National Institute of Health found that a person who smokes five joints per week may be taking in as much tar and cancer-causing chemicals into their lungs as someone who smokes a pack of cigarettes every day.
- Smoking marijuana weakens the immune system, and raises the risk of lung infections. Other studies indicate that smoked marijuana causes cancer, respiratory problems, increased heart rate, loss of motor skills, and damage to the immune system.
- According to several recent studies, marijuana use has been linked with depression and suicidal thoughts, in addition to schizophrenia. These studies report that weekly marijuana use among teens doubles the risk of developing depression and triples the incidence of suicidal thoughts.
I have not sought to check or question the references cited for these statements, but I am inclined to take the claims at face value. In addition, building largely on these sorts of medical claims while making a few other arguments, here are links to a couple notable and prominent commentaries making the case in favor of marijuana prohibition:
- Bob Enyart, "Why Marijuana Should be Illegal" appearing in the Huffington Post (dated 3/19/2012)
- Kevin A. Sabet, "The Price of Legalizing Pot is Too High" appearing in the Los Angeles Times (dated 6/7/2009)
Last but certainly not least, the Director of the Office of National Drug Control Policy, R. Gil Kerlikowske, gave this notable public statement to California Police Chiefs Association Conference in March 2010 titled "Why Marijuana Legalization Would Compromise Public Health and Public Safety." Here is how he summed up his main arguments against marijuana legalization at the start and tail end of this speech:
The concern with marijuana is not born out of any culture-war mentality, but out of what the science tells us about the drug’s effects. And the science, though still evolving, is clear: marijuana use is harmful. It is associated with dependence, respiratory and mental illness, poor motor performance, and cognitive impairment, among other negative effects....
Legalizing marijuana would also saddle government with the dual burden of regulating a new legal market while continuing to pay for the negative side effects associated with an underground market whose providers have little economic incentive to disappear....
Legalization means the price comes down, the number of users goes up, the underground market adapts, and the revenue gained through a regulated market will never keep pace with the financial and social cost of making this drug more accessible.