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What I learned from the Casey Anthony Trial

Back in March, cadaver dog handlers everywhere spent hours watching  on YouTube the pre-trial hearings for the Casey Anthony murder trial. The trial reinforced two things for me: the importance of good records and the need for more double blind problems.

Officer Jason Forgey testifying at the Casey Anthony trial
Officer Jason Forgey testifying at the Casey Anthony trial

I felt the strongest empathy for K-9 handler Jason Forgey especially what happened on  3/24/11.    His training logs were examined in detail and the issue of blind problems came up. Officer Forgey’s testimony would have been much stronger if he had more blind problems in his training records.  But exactly what kind of blind problems?

The defense attorney didn’t seem to know the correct definition of a double-blind problem.   Neither him or Officer Forgey every used to term correctly and I’m pretty sure that they are not alone.  The blind problems that they called “double blind” in the court record were really ” single blind”  problems. What’s the difference?

Simplifying a bit here, there are three types of training exercises.

1. Known problem.  The handler knows where the target odor is hidden.

2. Single Blind problem. The handler does not know the location of the target odor. The evaluator does.  This is the most common type of “bind” problem, including testing scenarios.

3. Double blind problem.  Neither the handler nor the evaluator know the location of the target odor. A third person sets up the scenario and that person is not present during the test.

With known problems, handlers can inadvertently cue their dogs and this can make dogs seem more reliable than they really are.  (see Lit, Schweitzer and Oberbauer for a recent example).   Single blind problems seem like the answer.  But, they aren’t.  The same subtle and non-conscious cuing between handler and dog that we  all know about  can also take place between handler and evaluator.  A good trainer doesn’t give the problem away on purpose. She keeps her game face on.  But the circle of people we train with is fairly limited and over the years, like a good poker player, we learn to read each other.  You learn everyone’s  “tells” even if you can’t describe them explicitly. You just have a feel for when you are getting warmer, and when you are cold and you are right often enough.

It gets worse.  What applies between handlers and evaluators applies to dogs and evaluators as well. If dogs can predict seizures, it stands to reason that they can learn to detect whatever subtle changes in vital signs and body chemistry in evaluators and observers. Dogs read everyone’s ‘tells” or cues.   And these cues may become reinforcers.    Without saying a word, the evaluator may be shouting out,

“Yes, you are getting warmer. Be confident. Go ahead and do your trained indication.”   We have all heard that trained final responses may be more subtle outside of training.  Our trainers warn us not to expect a great final response in the field.  A certain type of dog may come to rely on the inadvertent cues given by the people who know where the source is hidden and their behavior outside of training may suffer.

We must be able to field dogs that work independently.   Not biased by the emotions and body language of the handler, or anyone else at the scene of a search.More and more, I think the only way we are going to get that is to do a lot of double blind training.




Amir Findling

I have to disagree. Your argument is based on the “fact” that the dog might sense something. But what is shown is at best opinion, nothing that is backed by double-blind research!

Here is my opinion. I am trained a mantracker. My eyes see about as much a anybody else’s but my brain has learned to interpret the sign and make sense of it. As for the dog, his nose does indeed notice differences in body emanations but it will only be with training that the dog will be able to make sense out of it.

As for testing on double-blind problems, no problem with an occasional one, but making them frequent time, precious time, will be spent on problem setup and testing instead of training, and most learning come from training!

Finally, in the case mentioned, the handler is LE and thus I see his duty to train to the standard required by the courts (I did not say law). The volunteer, read unpaid SAT dog hanswer cannot be expected to be held to the level of standard of his paid counterpart.

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