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COA: dog sniff evidence need not necessarily be corroborated to be admissible

State v. Mark J. Bucki, 2020 WI App 43; case activity (including briefs)

[UPDATED POST – Scroll to the bottom for very useful commentary by Chris Zachar. Many thanks to him for sharing his knowledge.]

The headline tells you the only legal proposition you need to take from this soon-to-be-published case: under Daubert, evidence that trained dogs indicated the defendant had been at a particular location, and also that there had once been human remains in other locations, is not subject to a per se rule requiring corroboration before it can be admitted at trial. In a given case, a circuit court could conclude that particular dog-sniff evidence is not sufficiently reliable to come in (with or without corroboration). But Bucki’s argument–that dog-sniff evidence is so inherently unreliable that it necessarily requires corroboration–is rejected. We read the 50-page opinion, so you don’t have to.

The rest of the discussion (which also addresses related IAC claims, also rejected) could be useful in that it’s a lengthy, thorough analysis of Daubert methodology. Certainly if you have a case involving dogs that track people or sniff for evidence of cadavers or drugs, you’ll want to give it a look, both because it collects cases and because it discusses the claimed abilities of cadaver and tracking dogs at some length.

The fact-intensive nature of the opinion makes it tough to summarize. But the claimed abilities of these dogs are otherworldly: correctly identifying spots where a human body lay days, weeks, or many centuries ago. Maybe it’s real? We’ve looked for debunking articles in preparing this post but haven’t found any. Comments on that point are welcome.


{ 2 comments… add one }
  • Chris Zachar June 10, 2020, 8:24 am

    Here we go again, the magical police dog that can smell a ghost. I spent the better part of a week litigating this very issue in a homicide last year and have a huge set of briefs and transcripts for anyone who wants them. The so called science on residual odor is complete BS. I’d start with the source articles from Arpad Vass that these handlers frequently cite as a scientific basis for the ability of dogs to detect the odor of death even when there are no remains, or even DNA recovered. While frequently cited for the proposition that that the abilities of these dogs have been proven, Vass acknowledges that the variables on death odors are immense, and that the chemical compositions emitted from decaying bodies vary widely depending on composition, degree of decomposition, and environmental factors, so there is no universal odor of death, and the compounds that are consistent can be innocently shed from blood, hair, nails, teeth, and skin cells – so a dog alerting in a bathroom is expected in most cases. No reliable studies document when a body begins shedding the odor of death, I’ve searched exhaustively and only one extremely smallscale study from Scandinavia tried taking swabs from nursing home patients shortly after death to be tested only on one dog. The sample size was very small and only one dog (as I recall) was used. Moreover, dogs trained on cadaverine and putrescine are liable to alert to decay from ANY organic matter, including animals and even decaying mulch or bacteria.

    Additionally, most human remains dogs are not tested or certified for residual odor, and any training for residual odor is done off the books, usually with a huge amount of human remains to develop a smell (e.g. ten pounds of uncovered adipocere left in a hot car trunk for 24 hours) . Many of the local dogs are certified by NNDDA, and their certification protocols are all available online. Any handler who says their dog is certified for residual odor by NNDDA is lying. There are NO reliable methods to train on a body that spent a short period of time dead in a particular location. Handlers generally refuse to document these searched with instruments like a go pro or body cam because it allows us to challenge after the fact. In my case, the handlers testify that they don’t bring in dogs to see if they agree because they don’t want different results. So the actual position of these handlers is that this ‘scientific’ evidence does not require documentation and they do not have to search for disconfirming evidence. The entire use of these dogs to come to an untestable conclusion is the antithesis of the scientific method

    Check out the study on cueing by Lisa Lit, published in 2011 by the Journal of Animal Cognition. It found up to an 85 percent error rate on dogs and residual odor, simply by responding to the expectations of others present that something was there.

    Finally, on the issue of live scent ID. Various courts have recognized the lack of scientific reliability and excluded this evidence, including Texas, which executes more people than every other state in the US combined. Our Court of Appeals just endorsed the use of a method in Wisconsin that is too unreliable to use in Texas.

  • Chris Zachar June 10, 2020, 8:29 am

    One more comment. The National Innocence Project in New York is actively litigating the admissibility of residual dog odor in multiple jurisdictions, and has a collection of transripts, experts, and filings on this issue in multiple jurisdictions. They were very helpful in my case and I would highly recommend that anyone litigating this issue reach out.

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