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Cop Science is Junk Science

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Last week, I almost had my first trial. And it was going to be one of the most complicated cases to appear in Maryland District Court (which covers non-jury misdemeanor cases): a challenge to so-called Drug Recognition Experts.

Take this hypothetical scenario: a woman is pulled over for driving over a dividing line (“erratic driving”). The cop talks to her, asks if she’s been drinking. She denies it, but seems a little out of it. He asks if she’ll take a preliminary breath test, and she accepts. She blows a .00. The cop asks her out of the car to perform a “field sobriety test,” with mixed results; she stumbles a bit on the balance tests, and her responses to questions are a bit delayed. The cop asks if she is on any medication, and she responds that she takes insulin and prescription stimulants for various medical disorders, and has taken them for years. The cop then arrests her for driving under the influence.

At the police station, the woman is examined by a Drug Recognition Expert. The DRE is just another cop, but with some additional training. The DRE asks her some questions, checks her vital signs, and examines her eyes. He then looks at the DRE Matrix, which contains a list of symptoms as they relate to each type of drug. The DRE then diagnosis the woman as under the influence of a CNS stimulant, and the case goes forward to trial. At trial, the DRE testifies that the woman was driving while impaired by a CNS stimulant, and not impaired for any other drug, medical condition, or physical circumstance. There is no other evidence of drug-induced impairment. The court finds her guilty of DUI.

DREs are, in short, magic cops. In Maryland, they receive 10 days of training, most of that done by other cops or prosecutors. In a DRE case before mine where I sat second chair, the “expert” testified that he spent maybe a couple of hours during his training with an actual doctor. He had gone to college, where his major was accounting, and he had taken one course in biology. Yet after just 10 days of training regarding the different types of drug (both legal and non-legal), the DREs are supposedly able to diagnose someone as impaired by a specific type of drug, excluding all other possible causes, including medical conditions. In my hypothetical case, the DRE would testify that the woman was impaired by a CNS stimulant and not by, for example, low blood sugar. Because they have zero knowledge or training in medical conditions, and do not even have access to the suspect’s medical history during their “examination,” this borderline-supernatural ability presumably comes about through magic.

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An example of a DRE matrix. Note the overpowering odor of feces.

It is bulltrout. Not just ordinary bulltrout either, but flagrant, brazen bulltrout. Medical doctors with three years of schooling and several more years of training would be tentative to make such a judgment, yet DREs claim to be able to do it easily after a 10 day seminar of cops and prosecutors, with a couple of hours chatting with a doctor. Yet, like most cop sciences, courts are eager to accept their conclusions. “Cop science” means “science” that is completely made up by law enforcement with little to no backing in the scientific community. Law enforcement has a history of making up trout in order to make investigating and prosecuting people easier, including fabricating science-sounding techniques that are in fact pulled out of their collective ass. The field sobriety test (stand on one foot, say the alphabet backwards, etc.) is one such cop science, albeit a less harmful one. But another cop science with a HUGE impact on the criminal justice system is drug-sniffing dogs.

Cops rely on drug dogs all the time, and courts readily accept a drug dog’s alert as sufficient probable cause to justify a search of someone and/or their property. And of course that’s justified, right? K9 units are everywhere, searching for drugs or bombs or tracking down suspects. Dogs have an incredible sense of smell which has been relied on by humans for centuries. Surely drug dogs are reliable.

And drug dogs are reliable… at least, if you consider flipping a coin to predict the presence of drugs to be reliable as well.

In reality, drug dogs are incredibly unreliable. The significant independent studies (see pages 4-9) regarding the accuracy of drug dogs are filled with findings on how unreliable they are. And yet drug dogs go through extensive training and retraining by law enforcement to earn their qualifications. How does that add up?

Well, the training is bulltrout. It is routinely not double-blind (meaning that the handlers know where the drugs are), which is hugely significant. Because dogs not only have an incredible sense of smell, but they also are extremely sensitive to body language, which is their primary method of communication with other dogs. Dogs are very sensitive to their handlers actions and expectations; even if a handler is not intentionally trying to encourage a dog to alert, the dog can read the handler’s body language. This isn’t just speculation either, as studies have shown that the handler’s belief has the most impact on whether a drug dog alerts. In the field, when a police officer is expecting to find drugs, the dog will react to those unconscious signals (or even conscious ones in the case of some cops). And where the handlers are just as oblivious as the dogs as to the presence of drugs, a drug dog’s alert is simply inaccurate.

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Sorry, Fido. You're actually useless.

Recognizing this, a couple of years ago the Florida Supreme Court issued a groundbreaking decision that held that a drug dog’s alert is NOT by itself sufficient for probable cause unless the handling officer testifies to the dog’s reliability through field data – the dog’s hits and misses in actual cases. This does not solve the problem, as police routinely record a dog’s alert as accurate if there is any indication that drugs were ever on a person or in a car (the dog is then detecting the “residue”), but it would be a big step forward.

Unfortunately, just last month the US Supreme Court reversed the FSC’s decision, ruling that a drug dog’s training by itself can render the dog reliable. There was one opening left: apparently the trial defense attorney did not challenge the legitimacy of the dog’s training, that argument was waived on appeal, and SCOTUS did not address it. Even so, challenging the drug dog culture is an uphill battle. It may even be futile.

Fortunately, challenging DREs does not look quite so hopeless. Locally, there was a comprehensive case consolidating over a dozen felony cases in another Maryland county, where a Circuit Court judge found that DREs are junk pseudoscience and their conclusions should not be admissible. The full opinion is here (I had trouble viewing the file on my browser, but I could view it in Acrobat Reader after downloading the .pdf). Other courts and states have accepted DREs based on ridiculous premises, such as accepting law enforcement organizations as the relevant scientific community that DREs need to be accepted by in order to be valid. But with the great weight of evidence and the scientific and medical community nearly uniformly on one side, future challenges are not quite so bleak. Hopefully this is one cop science that can be forever killed off, but there’s still a long ways to go.

Updated 03-18-2013 at 05:18 AM by Raistlin

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  1. fire_of_avalon's Avatar
    I had no idea that was even a thing.

    But don't advertise in my VMs when you don't ever text me no mo.
  2. Raistlin's Avatar
    Man, you're needy. *texts*
  3. Formalhaut's Avatar
    I think you're a born lawyer.
    Updated 03-12-2013 at 10:28 PM by Formalhaut
  4. Quindiana Jones's Avatar
    I have a friend who works as a magic police shaman. He wanted to become a proper doctor, so he did a bit of studying and decided to apply for medical college. Unfortunately, he completely bombed, so he's....

    Still DRE.
  5. Teek's Avatar
    Reading this bothered me in a way I wasn't expecting. How many more instances can you think of where legal frivolities get in the way of actual science?

    I feel remarkably unsafe, now. And I don't even do drugs.
  6. CimminyCricket's Avatar
    Quote Originally Posted by Raistlin
    asks if she’s been driving. She denies it
    Just had to point out this bit because it made me laugh.

    Speaking on experience having worked in both the defense and prosecuting side of the military law system (as well as spending some time under a judge) and working as a military police officer I have to agree with your assessment that the stuff that is considered admissible in court is pretty crazy. While the Marine Corps has done away with with the ABC/ZYX test, we still use the balance on one foot, the walk on a line, and follow the finger tests as our field sobriety tests. A lot of what we rely on is not only the loss of balance, but the ability to follow directions. I think it's dumb, because even I have horrible balance depending on how I'm feeling that day and some people can be so irritated about being pulled over that they'll try and get it over with as quickly as possible. We get a few hours of classes and 'pratical application' that totals all of 4-5 hours max before we're moving on to the next area of study.
  7. Raistlin's Avatar
    Quin: was that supposed to be some horrible pun that went over my head?

    Teek: Don't even get me started about legal conclusions that are at odds with science. For one, there's the still ridiculously high sentencing disparity between possession for crack cocaine and powder cocaine (crack cocaine being punished at the federal level about 8 times higher, IIRC), despite them being the same goddamn drug; the only difference is that crack is a street drug used predominately used and distributed by poor urban blacks. Additionally, people have had their cash seized based on "evidence" of drug trafficking, where the only such evidence is drug residue found on the bills. That might sound ok at first, but studies have shown that drug residue is found on the vast majority of US currency.

    Cim: Yeah, the field sobriety tests have been completely made up. I consider that a much lesser evil, though, because usually those aren't considered without some other testing backing the evidence up (even if it's just a breathalyzer). The cases where DREs were challenged were where there was no other scientific proof of drug-induced impairment.
  8. Dr. rydrum2112's Avatar
    Raistlin is right on here, no one even talks about this stuff though- politicians can't because they can't seem to be anti-police or would never get elected.

    I also find it amusing that people still think eye-witness testimony is worth something.
  9. Quindiana Jones's Avatar
    No. It was a magnificent pun that went over your head. You need to listen to more Dr. Dre, man.
  10. CimminyCricket's Avatar
    You want to talk about eye witness testimony meaning something? In Afghanistan all we have to do is take a picture of someone restrained and with evidence scattered about them for the court to find them guilty.
  11. Raistlin's Avatar
    Eye-witness identifications can mean something, but ryd is right that it is grossly overestimated in many circumstances. Eye-witness IDs of strangers have terrible accuracy, especially for cross-racial identifications. Police lineups and photo arrays are also generally terrible and suffer from a variety of flaws and biases.