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The Unscientific Science of Jury Selection

The techniques of jury consultants are unreliable, and often incentivize the use of lazy stereotypes.
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(Photo: caliorg/Flickr)

(Photo: caliorg/Flickr)

In 2012, Jodi Arias was tried for the 2008 murder of her ex-boyfriend Travis Alexander, and her story was everywhere. The grisly details of Alexander’s murder, lurid details about their sex life, and the drama of their break-up were all revealed in the trial, live-streamed online. Lifetime even turned her case into a movie. Arias was convicted on first-degree murder, and, by the end of the year, a jury will determine whether she should be sentenced to execution.

Arias, like all defendants in the American court system, has the right to be tried by a jury of her peers. The assumption is that the collective wisdom of good, everyday citizens will result in a fair verdict. But this system was designed well before social psychologists discovered how pervasive humans’ biases are. In a popular case like Arias', jurors come to trial with their own knowledge about the case—on the first day of her trial’s sentencing phase, more than half of the potential jurors were dismissed, many because they knew too much about the case. Add that knowledge to jurors’ own opinions and experiences, and every juror is biased in some way.

He argued this wasn’t race-based, but rather that "Hindus tend ... to have feelings a good bit different from us" and that he preferred an "American juror."

If you’re a lawyer, you hope that you end up with jurors with biases that help your client’s case. Some attorneys are taking a more proactive tactic: They are hiring outside consultants who create a plan for selecting an ideal jury, and figuring out how to sway those jurors toward their desired verdict. The process is called “scientific jury selection.” Some consultants run mock trials to see if jurors’ characteristics predict verdicts. Others survey potential jurors about their beliefs and background to identify jurors who are least sympathetic to their client’s side, and they coach attorneys on how to convince them. The creepiest consultants complete full “pre-trial investigations” on potential jurors, which include background checks, interviews with acquaintances, and drive-by observations of jurors’ homes.

The first trial consultants were social scientists who wanted to help defend Vietnam protesters in a 1972 case. Since then, consultants’ presence in the legal system has grown considerably; as of the early 2000s, trial consulting was a $400 million industry. Like most consultants, they are paid handsomely, as much as seven figures per case. They’re indispensable in high-profile suits: Dr. Phil rose to fame when his trial consulting company represented Oprah in a lawsuit worth $12 million. (The Arias case may also involve consultants, but we can’t be sure: Consultants are not required to disclose their participation.) Critics raise concerns that these high fees mean only corporations or wealthy individuals can afford consultants, which widens the gap between the rich and poor in the courtroom.

SO, TRIAL CONSULTANTS ARE getting paid big bucks to craft an optimal jury, but how does scientific jury selection actually work? “Not very well,” says Neil Kressel, professor of psychology at William Patterson University and co-author of Stack and Sway: The New Science of Jury Consulting. “A lot of conditions have to be met in order for it to work.”

One of those conditions is whether jurors’ characteristics actually predict their decisions. Researchers have yet to identify consistent links between juror qualities and the outcome of a trial; it’s all highly contextual. “Figuring out who the jurors are is somewhat important, but research shows it matters less than the facts of the case,” Kressel says. Mock trials have found that scientific jury selection only works better than traditional jury selection when juror characteristics are highly related to a specific verdict—for instance, a person who has had a family member die in a car crash may be more partial to car crash victims.

Trial consultants concede that data don’t always help them choose juries. Rather, they credit their success to years of experience. Jo-Ellan Dimitrius, the trial consultant hired for O.J. Simpson’s trial, wrote that “reading people is neither a science nor an innate gift,” and that “intuition ... has always played a major part in my work.” A sixth sense for lying or biased jurors would be an asset, but research shows that people are actually pretty bad at reading others. One review of over 200 lie-detection studies found that, on average, people correctly identify only 47 percent of lies, and 61 percent of truths. Even worse, incredulous consultants may be especially susceptible to deception: One study found that skeptical people are less likely to detect lies.

According to Kressel, the other pre-condition for successful scientific jury selection is how much power attorneys have to eliminate jurors. Attorneys can’t handpick jurors, but they can exercise peremptory strikes—dismissing jurors without explanation. If consultants find those specific characteristics that predict the trial’s outcome, they can use their strikes strategically to eliminate jurors who may be biased against their side. The more strikes a judge allows, the more opportunity for consultants to influence who ends up on the jury.

Even if consultants succeed at identifying jurors who are biased against their side, attorneys may not be able to strike them. The Supreme Court ruled in Batson v. Kentucky that jurors cannot be struck on the basis of their race or gender. There’s a fairly easy way around this, though—historically, attorneys circumvent the rule by using neutral but heavily coded justifications. For instance, Judge Mark W. Bennett reported that a prosecutor in a federal district court dismissed a juror of color, who he presumed to be Hindu. He argued this wasn’t race-based, but rather that “Hindus tend ... to have feelings a good bit different from us” and that he preferred an “American juror.” Though this justification is technically based on religious beliefs, it’s pretty transparently about racial stereotypes. This came up in the Arias case, too: The defense alleged that the prosecution systematically eliminated black and female jurors, but the judge accepted the prosecution’s race-neutral explanations at face value.

Some argue that consultants exploit this loophole by twisting their data to find “race-neutral” arguments. Race and gender can be correlated with other characteristics, like native language or beliefs, which are accepted justifications for strikes. On the other hand, consultants’ findings could help eliminate race- or gender-based selections. Research suggests that asking jurors detailed questions actually decreases the possibility that attorneys strike based on surface characteristics like race or gender. Plus, if consultants find no correlation between demographics and verdict, attorneys’ strikes could be genuinely race- or gender-neutral.

ULTIMATELY, IT COMES DOWN to the motives of attorneys and consultants themselves: The information could be used to eliminate bias or disguise it. Kressel points out that as long as we’re in an adversarial legal system, lawyers have an incentive to use juror data and peremptory strikes to their advantage. “They have a legal obligation to be doing everything they can within the law to advocate for their position,” he says. “I don’t think ethical lawyers are the answer [to unbiased jury selection]; the rules need to be fair."

Fair rules have been suggested, but not implemented. Some believe that judges should increase transparency by requiring consultants to share their juror data with both sides. To level the playing field, courts could appoint trial consultants for people who cannot afford to hire their own, or require consultants to complete pro-bono work. Kressel and other scholars suggest doing away with peremptory strikes altogether. Instead, courts could revise standards for allowing challenges for cause, which require attorneys to justify why they want to disqualify a specific juror.

Either way, scientific jury selection is here to stay. Perhaps the best-case scenario is that it doesn’t work that well; after all, if consultants can mold juries and shape verdicts, they would also hold the power to win a trial before it begins.