Defending People

the tao of criminal-defense trial lawyering

Murphy’s Law of Investigation

From today’s Hous­ton Chron­i­cle:

DNA evi­dence — col­lected in 2002, but unex­am­ined until now — has cleared [RR,] a Hous­ton man serv­ing a 40-year prison sen­tence for the sex­ual assault of a child.

The com­plainant (the Chron­i­cle calls him “the vic­tim”, but in this case that term is ambigu­ous) who iden­ti­fied RR had, when describ­ing his assailant, not men­tioned RR’s very con­spic­u­ous facial dis­fig­ure­ment, caused by a shot­gun blast years before.

RR’s case brought to mind Murphy’s Law of Investigation:

Enough inves­ti­ga­tion will tend to sup­port your theory.

I cribbed that from Murphy’s Law of Research (“Enough research will tend to sup­port your the­ory”). The prin­ci­ple behind Murphy’s Laws of Research and Inves­ti­ga­tion is con­fir­ma­tion bias, the human ten­dency to seek out and rec­og­nize the data that sup­port their pre­con­cep­tions, and to avoid data that chal­lenge those preconceptions.

Could con­fir­ma­tion bias have con­tributed to RR’s con­vic­tion? It’s often the case that a pros­e­cu­tor will have made up her mind about an accused’s fac­tual guilt before even read­ing the offense report; the pros­e­cu­tor in RR’s case was not inter­viewed for the Chron­i­cle arti­cle, but could that have hap­pened here?

Might a pros­e­cu­tor who hadn’t already decided that RR was the right guy have been more dili­gent in look­ing for evi­dence? Might such a pros­e­cu­tor have dis­cov­ered in 2002 that there was a rape kit, with DNA to try to match against RR’s?

Might RR, as a result, have spent the last six years a free man?

The pros­e­cu­tor may have counted on the defense lawyer to run down all of the pos­si­ble excul­pa­tory leads. But some­times lawyers for­get that often cops and pros­e­cu­tors get the wrong guy. Can you imag­ine a defense lawyer shar­ing the prosecutor’s pre­con­cep­tion that RR was fac­tu­ally guilty? Could con­fir­ma­tion bias have lead such a defense lawyer not to go to the trou­ble to find out whether the DNA recov­ered from the com­plainant matched RR’s?

Which brings us to this, from Dal­las criminal-defense lawyer (and ex-prosecutor) Robert Guest:

When I was a DA I had pro­fes­sional state wit­nesses (cops, intox experts) and my own team of inves­ti­ga­tors. There was also the feel­ing that the appel­late courts worked to ben­e­fit the State and uphold con­vic­tions. Defense experts and the­o­ries were largely mocked and dis­missed at my train­ing seminars.

Only as a defense attor­ney did I learn why and how field sobri­ety test­ing is flawed, what the lim­i­ta­tions of intox­i­lyzer machines were etc.

That’s con­fir­ma­tion bias at work: Robert didn’t, as a pros­e­cu­tor, learn why and how field sobri­ety test­ing was flawed because his job was to pros­e­cute peo­ple, and find­ing rea­sons to chal­lenge his own evi­dence didn’t help him do that job.

We all have pre­con­cep­tions and prej­u­dices formed by our life expe­ri­ences. Any of us might unknow­ingly suf­fer from con­fir­ma­tion bias that helps us main­tain these pre­con­cep­tions, even if they’re wrong. A pros­e­cu­tor might right­fully assume that a per­son accused of a crime com­mit­ted that crime because — let’s face it — the cops usu­ally get things right, and in the small per­cent­age of cases in which the wrong guy is arrested there’s a defense lawyer who will fight zeal­ously to pre­vent an injustice.

But, no mat­ter how jaded, a defense lawyer can’t assume that the cops got it right because — let’s face it — the cops often don’t get things right, and in those cases the defense lawyer had bet­ter not be pre­vented, by con­fir­ma­tion bias or any­thing else, from seek­ing out the evi­dence that might save the accused from prison or death.

It bugs me a bit when (rarely) clients ask whether I believe they are inno­cent. It doesn’t mat­ter to me, and I haven’t made up my mind. Besides, I think the ques­tion is a sign of a guilty con­science; when I’m try­ing to defend some­one I don’t need him pre­sent­ing me with evi­dence of his guilt (con­fir­ma­tion bias!).

But you can see how it would ben­e­fit the accused for his lawyer not to come to the job with the pre­con­cep­tion that the accused com­mit­ted the crime of which he was accused.

(It is, inci­den­tally, sub­op­ti­mal for the criminal-defense lawyer to uncrit­i­cally decide that the accused didn’t do the deed, because that might — con­fir­ma­tion bias again — get in the way of his red team­ing the case.)

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About The Author

Mark Bennett got his letter of marque from the Supreme Court of Texas in May 1995. He is famous for having no sense of humor when it comes to totalitarianism.

Comments

8 Responses to “Murphy’s Law of Investigation”

  1. I run into it in DWI cases — the offi­cer writes his report after the fact so he empha­sizes the signs of intox­i­ca­tion and largely ignores signs of sobriety.

  2. Ron in Houston says:

    Well, there is con­fir­ma­tion bias but there also is sleaziness.

    It is dif­fi­cult to check our­selves for all our flawed cognitions.

  3. PJ says:

    There is never any rea­son for any lawyer involved in the crim­i­nal jus­tice sys­tem to ever make a con­clu­sion about a defendant’s guilt or inno­cence. It’s not nec­es­sary to per­form any such lawyer’s job and can only wreak havoc. The defense lawyer who fights harder for a client because he believes that client is inno­cent is pro­vid­ing a dis­ser­vice to all his other clients (some of whom the lawyer may have erro­neously concluded–on the basis of lit­tle information–were not inno­cent). The pros­e­cu­tor who judges will be infected by con­fir­ma­tion bias and will be unable to per­form her statu­tory and con­sti­tu­tional duty to see that jus­tice is done. She will equate “jus­tice” to see­ing the per­son she has per­son­ally adjudged “guilty” being con­victed, short­cir­cuit­ing the prosecutor’s true pro­fes­sional role of being a pro­ce­dural and evi­den­tiary vessel.

    The duty to see that jus­tice is done has noth­ing to do with the guilt or inno­cent of the defen­dant, even less with con­vict­ing the guilty. It con­tem­plates only the lawyer’s pro­fes­sional duties, pro­ce­dural (is this evi­dence excul­pa­tory such that it must be dis­closed?) and evi­den­tiary (is this evi­dence legally and fac­tu­ally suf­fi­cient to present to a jury at a trial).

    Lawyers don’t decide guilt or inno­cence. They present evi­dence to juries (or, when requested, judges) to decide guilt or inno­cence. The lawyer (pros­e­cu­tor or defense lawyer) who takes it upon him­self to play the role of judge only need­lessly com­pli­cates his job and puts the lib­erty of cit­i­zens at risk. This is espe­cially per­ni­cious when pros­e­cu­tors take it upon them­selves to judge whether defen­dants deserve to live or die in cap­i­tal cases.

  4. Mark Bennett says:

    I don’t entirely agree with you, PJ.

    A lawyer’s job is to tell the client’s story. Since there are gen­er­ally sev­eral sto­ry­lines that could lead to the result the client seeks, the lawyer has to pick the one that will be most effective.

    A jury is an excel­lent detec­tor of insin­cer­ity, so the client is bet­ter off if the lawyer is telling a story that he believes or, put dif­fer­ently, if the lawyer believes he is telling the truth.

    If the lawyer doesn’t believe the story he’s telling, why would he hope the jury will?

  5. ADA says:

    Jimmy Ortiz was the DA on this case; and he is now a Defense Attor­ney. I am inter­ested to hear his thoughts on this case and why the DNA was not tested.

    Kudos to all those (both Defense bar and ADA) who are work­ing on review­ing the cases and sift­ing through the boxes of materials.

  6. As usual, being more than will­ing to flaunt my igno­rance, a hypo­thet­i­cal: so you’ve got a guy who is accused of some­thing where there’s an untested rape kit that may or may not clear him. He says he’s not guilty by rea­son of he didn’t do it, but you may have heard that from a client before where it turned out to not nec­es­sar­ily be accu­rate, and you’re not sure you believe him. But you think you’ve got a decent chance to beat the charge at trial, as things stand.

    If you open Schroedinger’s rape kit, you’re pretty sure that either a: he walks, or b: it’s over, ’cause he’s going to be con­victed. There is no reverse Brady oblig­a­tion; you don’t have to point out to the pros­e­cu­tor that there’s this untested rape kit, that you think he or she over­looked. Since you decide that this is a deci­sion you have to run past your client, he says, hey, I didn’t do it, but I trust you to do the right thing for me.

    Isn’t there at least an argu­ment that you leave it alone, at least until the jury comes back?

  7. Mark Bennett says:

    ADA, I’ve talked with Jimmy Ortiz; with the pas­sage of time he doesn’t have enough rec­ol­lec­tion about this case to answer his own ques­tions about it. Tammy Thomas appar­ently tried the case with Jimmy.

    Joel, that seems to fall within the cat­e­gory of tac­ti­cal deci­sions that the lawyer gets to make. Leav­ing it alone until the jury comes back might make sense, under the cur­rent law, if you don’t believe your client’s asser­tions of inno­cence but think you can swing an acquit­tal any­way. If your hunch ulti­mately proves wrong (if he’s con­victed and the DNA clears him), all (!) he has lost is a few years in the hell of Texas prison.

    If I tell a client, “look, if you didn’t do it, then this DNA evi­dence will most likely clear you, but if you did, then this DNA evi­dence will most likely con­vict you; I don’t have to get it tested, but I will unless you object” and he objects, I think I’ve done what I can to make sure he’s telling me the truth. But this is prob­a­bly a deci­sion that should be doc­u­mented with a let­ter to the client so that it’s clear that he’s been advised of the pos­si­ble bad outcomes.

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