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Univ. of South Carolina School of Law

Tuesday, July 10, 2012

Let Sniffing Dogs Lie?: Leslie Shoebotham's Brief Of Amici Curiae In Jardines v. State, Drug-Sniffing Dogs & False Positives

Accordingly, the use of a well-trained narcotics-detection dog—one that "does not expose noncontraband items that otherwise would remain hidden from public view," Place, 462 U.S., at 707, 103 S.Ct. 2637—during a lawful traffic stop, generally does not implicate legitimate privacy interests. In this case, the dog sniff was performed on the exterior of respondent's car while he was lawfully seized for a traffic violation. Any intrusion on respondent's privacy expectations does not rise to the level of a constitutionally cognizable infringement. Illinois v. Caballes, 543 U.S. 405, 409 (2005).

In sum, a "sniff test" by a drug detection dog conducted at a private residence does not only reveal the presence of contraband, as was the case in the federal "sui generis" dog sniff cases discussed above, but it also constitutes an intrusive procedure that may expose the resident to public opprobrium, humiliation and embarrassment, and it raises the specter of arbitrary and discriminatory application. Given the special status accorded a citizen's home under the Fourth Amendment, we conclude that a "sniff test," such as the test that was conducted in the present case, is a substantial government intrusion into the sanctity of the home and constitutes a "search" within the meaning of the Fourth Amendment. As such, it warrants the safeguards that inhere in that amendment—specifically, the search must be preceded by an evidentiary showing of wrongdoing. Jardines v. State, 73 So.3d 34, 49 (Fla. 2011).

So, according to the United States Supreme Court in Caballes, the use of a drug-sniffing dog around an automobile is not a "search" for Fourth Amendment purposes while, according to the Florida Supreme Court in Jardines, the use of a drug-sniffing dog at the front door of a house is a "search" for Fourth Amendment purposes requiring probable cause. This thus explains why the United States Supreme Court granted cert in Jardines to resolve the following issue: Whether a dog sniff at the front door of a suspected grow house by a trained narcotics detection dog is a Fourth Amendment search requiring probable cause?

In response to the cert grant, Leslie Shoebotham, an Associate Professor at the Loyola University New Orleans College of Law has written a terrific Brief of Amici Curiae Fourth Amendment Scholars in Support of Respondent, 2012 WL 2641847 (2012), arguing in favor of the conclusion of the Supreme Court of Florida that a dog sniff at the front door of a house is a Fourth Amendment "search." In many ways, the brief is an extension of Professor Shoebotham's great article, Has the Fourth Amendment Gone to the Dogs?: Unreasonable Expansion of Canine Sniff Doctrine to Include Sniffs of the Home, 88 Or. L. Rev. 829 (2009), which I wrote about here, and I was happy to be one of the professors to sign onto her brief. In this post, I will (1) detail some of the examples used by Professor Shoebotham to explain her argument and then (2) include her own summary of the brief. 

In Kyllo v. United States, 533 U.S. 27 (2001), the United States Supreme Court held that the use of a thermal imaging device to monitor the radiation of heat from a home was a Fourth Amendment search. In its aforementioned opinion in Caballes, the Court subsequently noted that "[c]ritical to [the Kyllo] decision was the fact that the device was capable of detecting lawful activity - in that case, intimate details in a home, such as 'at what hour each night the lady of the house takes her daily sauna and bath.'"

So, how likely are drug-sniffing dogs to detect lawful activity? That is the main question that Professor Shoebotham addresses in her brief, with her general point being that "[s]tudies show that drug-detection dogs alert to certain volatile substances that are found in street drugs, not the illegal drug itself." So, let's then get to specifics.

Cocaine and Methyl Benzoate

Let's say that a drug-sniffing dog is sniffing for cocaine. "In cocaine, methyl benzoate is a decomposition product or break-down product that is produced when cocaine hydrochloride is exposed to humid air." Some drug-detection dogs are trained to alert exclusively to methyl benzoate while others "undergo field training for cocaine detection using methyl benzoate training devices." So, what else contains methyl benzoate?  As Professor Shoebotham notes,

Snapdragons. Petunias. Perfume. Food additives. Cocaine. Common to all of these items is methyl benzoate, also known by its more "romantic" name, Oil of Niobe.

This can create false positives because "methyl benzoate is found in such abundance in household sources that it surpasses a detection dog's sniff threshold."

Heroin and Acetic Acid 

Or, let's say that a drug-sniffing dog is sniffing for heroin. "Studies show that acetic acid is the dominant odor signature of heroin and is the organic compound to which drug-detection dogs alert." Again, Professor Shoebotham points out that this creates a problem:

Vinegar. Aspirin. Food additives. Wart removers. "Green" or "Earth-friendly" household cleaning supplies. Heroin. Common to all of these items is acetic acid. 

Other Illegal Drugs

What if a dog is sniffing for MDMA, commonly known as "Ecstacy." Drug-detection dogs alert do not alert to MDMA but instead alert to the volatile molecule, piperonal, which

appears in a wide array of ordinary household products, like (1) soap,...(2) food additives and flavor enhancers,...(3) even lice repellents.

And how about marijuana? Professor Shoebotham notes that "while 'interference' studies exist there is otherwise no empirical data on canine marijuana detection and the related issue of whether 'smell-alike'plants exist that could produce a positive canine alert." That said, there is at least anecdotal evidence of false positives. For example,

In Britain, a pink flowering plant, called moss phlox, when grown in suburban gardens has produced positive canine drug-detection alerts and police raids on homes. 

Professor Shoebotham's Own Take

The above drives home Professor Shoebotham's main point: that there drug-sniffing dogs are clealy capable of detcting lawful activity, which means that, pusuant to Kyllo, drug sniffs of the front doors of houses should be deemed Fourth Amendment searches. Here is her summary of the brief:

The Fourth Amendment Scholars Amici Brief considers the scientific literature concerning canine drug-detection sniffs and analyzes how those findings impact the legal analysis of canine sniffs of the home.  To show that drug-detection sniffs are capable of revealing lawful activity within a home, the Brief uses published scientific studies which establish that in most cases drug-detection dogs are unable to detect the contraband itself, but instead alert to the presence of volatile break-down products of the contraband.  Importantly, these break-down products are not illegal and are not even unique to contraband.  In fact, these alert-producing molecules and compounds are found in substantial quantities in the ordinary home.  Using scientific studies that measure canine detection thresholds for these alert-producing substances, the Brief then juxtaposes those detection thresholds against the amounts that these molecules and compounds appear in ordinary household items.  Because these alert-producing substances are found in household items in amounts that exceed a detection dog’s alert threshold, the Brief argues that a canine drug-detection sniff of a home is capable of revealing lawful activity within the home, and is therefore a "search" under the Fourth Amendment. 



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Let me play Devil's Advocate for a bit.

The problem with this line of thinking is that it effectively bans dogs from sniffing for illegal drugs. The only thing a dog can sniff for is chemicals. It doesn't know what cocaine is; it can't. It doesn't know what ecstasy is; it can't. All it can do is sniff for chemicals; that's the only ability nature has given it; not higher order thinking skills. It would be the equivalent of banning the DNA machine because it doesn't know what DNA is....and DNA certainly has legal, lawful purposes.

The key aspect of Kyllo v. United States is that thermal imaging systems are incapable of detecting any illegal activity at all. All they do is detect heat. It's up to the operator to determine the significance of those heat sources. That interpretation is an intrusive act because it requires the collection of data that is unrelated to the investigation at hand. A dog sniff doesn't do that. There is no interpretation by the dog-handler; it's a binary yes or no. What's intruding is not the person but the instrument, the dog.

When it comes to these cases the key aspect is the level of intrusiveness of the search. A thermal imaging systems is highly intrusive. A dog sniff is not. The fact that the dog can sometimes be "wrong" by producing false positives is beside the point unless it is possible to demonstrate that these errors arise frequently. The question isn't whether the fruit of the search was tainted only whether the search was unreasonable to begin with.

Posted by: Daniel | Jul 10, 2012 5:05:58 PM

Daniel said:
"The fact that the dog can sometimes be 'wrong' by producing false positives is beside the point unless it is possible to demonstrate that these errors arise frequently."
Thankfully Daniel, it IS possible. On average, these dogs are reliable far less than 50% of the time, with the majority of such tests coming out in the 26% to 40% range. Worse still, some police are apparently using this tactic as an excuse to search a vehicle any time they want to, by claiming when the dog alerted when in reality nothing of the sort occurred.
Case in point: http://www.youtube.com/watch?v=rJqq6KCOkdM

Posted by: Scott | Jul 23, 2012 1:34:32 PM

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