Law, Justice, and Data

by on November 11th, 2004

A lawyer friend emailed last week to say he has a new book coming out in January. James Doyle’s True Witness: Cops, Courts, Science and The Battle Against Misidentification focuses on the history of the legal system’s resistance to psychological research on memory in general and eyewitness memory in particular. Doyle is a national expert on the vagaries of eyewitness testimony, a subject most often in the news these days when DNA evidence proves the inaccuracy of all those eyewitnesses whose overconfident testimony helps send innocent people to Death Row.

By coincidence, also last week the Boston Globe reported this item about the influence of psychological research on death-penalty cases:

A federal judge in Boston has ruled that if juries convict two alleged gang members of murder next year, different juries must decide whether the men should get the death penalty. US District Judge Nancy Gertner said the usual practice of a single jury considering both guilt and punishment tips the balance unfairly toward conviction, because people who oppose the death penalty are disqualified from serving on juries in capital punishment cases.

The Globe story describes the situation well:

Ordinarily, capital cases in federal and state courts are divided into two phases. Before a jury is chosen to consider guilt, prosecutors have the right to disqualify any potential juror who opposes capital punishment and would be unable to vote to put a convicted defendant to death. But lawyers for [the two defendants] … said that a growing body of evidence shows that purging such jurors produces a panel that is disproportionately white and male and more likely to convict defendants.

Gertner agreed. “Updated data presented by defendants in this case overwhelmingly shows that death-qualified jurors are significantly more conviction-prone than jurors who are not death-qualified,” she wrote in her order Wednesday.

Back during my psychology/law post-doctoral days at the University of Nebraska, the data Gertner refers to about conviction-prone death-penalty juries was already being accumulated, though it never seemed to me necessary. It seems obvious enough that requiring jurors to be pro-death-penalty leads to juries more likely to convict in the first place.

So-called “death-qualified” jurors are more likely than those excluded to be suspicious of defendants and people of color, trusting of police, and willing to err on the side of conviction. All of these biases counter the law’s theoretical assumption that a defendant is innocent unless proven guilty beyond a reasonable doubt. Too many jurors come into the jury room ready to convict unless the defendant can persuade them otherwise. It’s supposed to work the other way around.

The real advantage of having research-based data may be that judges like Gertner can say she’s simply following the evidence rather than letting her own biases affect her decision making. Again the Globe:

Gertner also said that although the US Supreme Court has ruled that using a single jury throughout a capital case passes constitutional muster, the high court never said the Constitution requires it.

Gertner’s own determination to do what she thinks make sense certainly comes into play. As I suspect Doyle may discuss in his new book, the law traditionally resists external influence. The Real World can easily muck up the purity of hard-nosed legal reasoning. That’s part of the reason law and justice have less to do with one another than most people like to think.

Massachusetts, where I live, has no state death penalty, but under the soon-to-be-departed John Ashbrook’s shift as U.S. Attorney General, federal prosecutors are forcing the death penalty on states whose own citizens don’t want them. By the time George W. Bush gets finished reshaping the federal judiciary over the next four years, judges like Gertner who try to humanize the law by incorporating reality-based justice concerns will be harder to find.

Dennis Fox