Over at Rick Horowitz’s blog, subtly named Probable Cause, a very interesting discussion broke out in the comments when a sheriff’s deputy named Larry took issue with Rick’s assessment of police testimony:

After a few years of working criminal cases, I now believe that all police officers will lie on the stand if they feel it is important to help the case.  Most police officers will tell the truth, unless they think by telling the truth the case will be hurt, or unless they think by telling a lie it will help the prosecution.  Even the most trustworthy police officers I’ve seen on the stand seem unable to resist “spinning” their testimony.

This spilled over into the comments, where Rick provided further explanation :

In cases involving gang evidence, as just one example, officers’ jobs very much depend upon how they testify. In courts around the area I practice, I’ve seen — and there are numerous stories from other attorneys both within and outside my geographical area — officers transferred after a particularly bad “showing” at trial. And if officers were not paid to obtain convictions, then how do you explain the gang cops who refuse to testify for the defense when asked because they’re afraid they’ll lose their jobs?

Larry didn’t care at all for this view.  More importantly, Larry, who described himself as a “Gang Expert” (his caps), decided to educate Rick.

The fact of the matter is, if the crime was not a gang crime and did not require my testimony or my expert opinion I would not take the case in the first place. Almost all gang officers are promoted or transfered into those positions because of their personal knowledge of particular gangs and their expertise with those gang members. Not because of good testimony. I will concede being able to testify is extremely important especially in gang cases because you are deemed an “expert” by the court and therefor can offer an opinion. This means you must be able to testify competently.

As for refusing to testify for the defense you made comment about “defense experts.” I am a Gang Expert. Meaning “I am a Gang Expert” not a “defense expert” nor a “prosecution expert.” I am a Gang Expert. If you perceived officer’s as truthful (which you should assume after all you assume your client is innocent) then you should have no problem with my testimony. As I stated earlier, if this was not a gang case I would not have taken it and this would be relayed to the district attorney’s office that the case is not gang related. Unfortunately, my testimony probably will not help you or your client therefor you perceive law enforcement as untruthful, dishonest and bias and in turn, you hire a “defense expert” to say what you want a jury to hear and to offer a different opinion for the benefit of your client. However, you and I both know that if I was going to offer an opinion that would benefit your client you would have no problem allowing me to offer such an opinion. However, to offer such an opinion would indicate that your client is not a gang member or did not commit the crime to benefit the gang and therefor I would be uninvolved in the case anyway.

The finest of circular reasoning notwithstanding, Rick then proceeds to explain why Larry’s police training and experience does not give rise to expertise in anything other than police training and experience.  Certainly not gang expertise, unless Larry was holding out on us by failing to disclose his former life as a gang member.  This fascinating debate offers a wonderful opportunity to discuss what it means to be an expert, who gets to decide whether someone is an expert, and why.

Expert testimony allows a witness to offer an opinion and respond to hypothetical questions.  It can be enormously powerful, since it feeds conclusions to the jury that the jury might otherwise have to make on its own, and for which the jury is arguably unprepared to decide due to its lack of specialized knowledge or experience. Staying with the gang theme, absent a juror with an interesting background that escaped notice in voir dire, how would they know that wearing a red baseball cap was a meaningful sign of gang involvement, or a meaningful sign of favoring a particular baseball team?

The problem arises from the fact that prosecutors require someone to say things that fill in the glaring gaps in their proof, but for which no evidence exists.  Enter Gang Expert to state with authority that the red baseball cap signifies membership in a criminal gang, and who can then go on to “explain” how gangs function, etc.  Amazingly, this tends to be wholly consistent with whatever evidence that prosecutor has.  How fortunate!

The problem, of course, is that there is no such “expertise”, except in the mind of the cop (like Larry).  And Larry, coincidentally, agrees by definition with the prosecutors assessment since, as Larry expressly states, he wouldn’t be there if he didn’t.  But remember that we have a judge sitting on the big bench, and the judge is the gatekeeper of all things expert.  To be admitted as an expert witness, the cop must first pass muster with the judge.

To do so, the prosecutor will ask the witness about his training and experience.  He will testify about the Academy, his additional training programs and his lengthy (or maybe not too lengthy) experience working the streets as part of an anti-gang group, where he has made (insert large and totally unverifiable number) arrests.  The judge pauses, says “hmmm”, then rules that the cop may testify as an expert.

Here’s the judge’s dilemma.  He knows that the prosecutor can’t make his case without the expert testimony, explaining to the jury the significance of the details that comprise the case.  He also knows that there’s no such thing as a “gang” expert, but that the cop is as close as the prosecution can possibly find.  His decision, therefore, means the difference between the case getting before the jury and the defendant getting a trial order of dismissal.  Bottom lining it, the judge isn’t going to toss the case.  If the defendant wants to win, it will have to come from the jury.

But what is the cop’s basis for expertise?  He’s been told by his brother police officers that a red baseball cap means gang membership.  He’s been told by his brother police officer how gangs function.  He goes out on the street, sees the red cap and busts the “gang member.”  Therefore, everything he knows is true because he acted upon it, and he would never have done so if it wasn’t.  That would be wrong.

And where did this fictional brother police officer who trains other brother police officers obtain this information and expertise such that it can be bootstrapped into reality in the courtroom.  They dunno.  They just take the class.  They don’t challenge the teacher.  That would be rude.  Cops aren’t rude.  At least not to other cops.

I’ve no doubt that Larry, poor Rick Horowitz’s foil, truly believes what he says.  And that’s a large part of the problem.  He is quite certain that he is an expert, that he knows what he’s talking about and that, by definition, he must be right because he would never have done it if he was wrong.  He would never “spin”, as he informed Rick (like defense lawyers do), because he takes absolute comfort in the correctness of his position.  It’s good to be on the side of truth and justice, even if only in one’s own mind.

Will Larry ever understand the Dunning-Kruger Effect?  Of course not.  Why would he bother?  Will the judge seriously consider the fact that Larry has no qualifications to opine as an expert, as if there actually were qualifications for such expertise?  Maybe, but only if the judge was prepared to put his own butt on the line should the defendant walk and commit a(nother) crime. 

What’s the lesson to be learned?  The only one I can think of is don’t wear a red baseball cap around Fresno.