Sunday, July 22, 2007

Judging and Misjudging Guilt and Innocence

Adam Liptak has a TimesSelect Column (July 23, 2007) in the NYTimes about a study of how well or badly the US criminal justice system ferrets out and corrects criminal convictions that rest on factual mistakes. The column focuses on a study by Professor Brandon L. Garrett of the University of Virginia School of Law. (The TimesSelect column provides a link to the copyrighted study, which is to be published in the Columbia Law Review.) A forthcoming study by Professors Samuel Gross (University of Michigan) and Barbara O’Brien (Michigan State) is also mentioned, but not discussed at length.

According to Liptak, one conclusion to be extracted from the Garrett study is that "[t]he courts performed miserably in ferreting out the innocent."

To the extent that Garrett's study discusses the rate of wrongful conviction of the innocent -- thus far I have only skimmed Garrett's paper --, Michael Risinger's paper (scroll down in the page to reach the link) should be consulted.

Liptak asserts, in passing, that "rape [is] the classic crime in which DNA can categorically prove innocence." This is a familiar mistake. But sophisticated observers such as Liptak should not make it. DNA cannot "categorically" prove innocence -- anymore than it can "categorically" prove guilt. For example, it is well known (or it should be well known) that (i) the presence of one male's semen in a woman's vagina does not rule out the possibility that another man raped that woman (whether the man who was the source of the semen found in the woman and tested did so or not) and (ii) a laboratory may have tested the wrong semen sample. Is it necessary to recite such possibilities? The fact that in particular circumstances the results of a DNA test may be highly persuasive evidence of innocence does not change the fundamental point: DNA evidence is NEVER conclusive of ANYTHING. Tiresome. And a dangerous misunderstanding.

Liptak notes that Garrett concluded that "[t]he leading cause of the wrongful convictions was erroneous identification by eyewitnesses, which occurred 79 percent of the time." What are we to make of this statistic? Does it matter how frequently eyewitness identifications resulted in the conviction of the guilty? (I assume Garrett discusses this point. [Let me emphasize that I have not yet carefully scrutinized Garrett's study. So I really am NOT saying or even intimating that Garrett has not discussed the questions I raise here.])

Note: unless one demands absolute factual certainty (which is unattainable under any circumstances), on the basis of the above-quoted statistic alone -- or on the basis of that statistic and the additional statistic that in 1/4 of the wrongful convictions eyewitness identification was the sole evidence --, on the basis of such statistics alone one would not conclude (I would think) (i) that eyewitness identification evidence should be barred or (ii) that eyewitness evidence alone should never suffice for a conviction. (However, further arguments and considerations might justify the latter conclusion -- the conclusion that eyewitness evidence [e.g., of just one eyewitness] should not be suffice for a conviction. [Again, I want to make crystal clear that I am NOT asserting that Garrett does not discuss such issues. I have not yet studied his study.])
I have lightly skimmed SOME parts of the Garrett study. The part of the study I enjoyed most (due, surely, in no small part to my personal theoretical prejudices) is the part in which Garrett stresses the importance of pretrial fact investigation and the substantial resources that are required (including, I would say, the diligence, discipline, and imagination of defense counsel) to conduct effective pretrial fact investigation.

2 comments:

Anonymous said...

What does one have to do to prove one's innocence of a crime he/she did not commit? We have been given the greatest investigative tool in the history of crime detection, and it has proven more valuable than fingerprints and outright eye-witness in capturing the actual perpetrators of crimes, and yet, and yet, some of those in authority, especially the police and prosecutors, have refused to acknowledge that DNA is the total key in solving crimes and bringing to justice those who actually commit crimes. Oh no, you say? OH YES, YES, YES! Ask all of those who were wrongly convicted of crimes others committed, and who were freed AFTER DNA was the key factor in establishing innocence. The true cases of exoneration through DNA tests are not anecdotal or hearsay; ask Barry Scheck for actual, factual cases. My son also applied to Barry Scheck's Innocence Project, which only accepts those cases involving DNA evidence alone, and my son told Mr. Scheck that he was accused, tried and convicted of murder DESPITE THE DNA THAT EXCLUDED HIM 100% AS THE PERPETRATOR.My son is one of many thousands of others who are waiting for his "turn" in the long list of others in such projects that do help innocent people. The police INSISTED AND the prosecutors PERSISTED, and my son is now serving LIFE WITHOUT THE POSSIBILITY OF PAROLE. He is awaiting his appeal, which is another black joke in Nevada, since it is common knowledge no one hardly ever gets, and our judicial system discourages justice in the first place. And just to make sure you know your place in society, prison inmates had better not dare to claim innocence or you will regret it and your family will regret it too.
Professor Garrett wouldn't touch this story with a ten-foot pole. And unfortunately neither will anyone else with the power to help just another victim of injustice.

sailorman said...

I suspect that the "categorical proof comment was made in the context of the witness' testimony. After all, the author didn't say "...DNA alone can categorically prove innocence."

For example, a woman testifies that she hadn't had sex in weeks, and was attacked in broad daylight, while sober, by a single man; was raped without a condom, and went straight to the police station.

The DNA of the semen doesn't match the accused.

Does this "categorically" remove the accused from consideration? It seems so.

Yes, obviously, nothing is perfect. Nothing is 100%. The test can be faulty; the witness could have somehow introduced other semen without being aware of it, etc etc.

But life is rarely subject to mathematical rigor. And when the alternate options become so unusual as to enter the realm of the ridiculous, then it is appropriate to say that the accused is "categorically innocent."