Dateline: June, 2021, Issue 4

How accurately do jurors self-diagnose their ability to be fair?

The judicial system weights a juror's self-diagnoses of bias and fairness during voir dire very heavily, assuming that, as a factual matter, jurors can undertake accurately this self-assessment.

In the context of a medical malpractice case, Yokum, Robertson and Palmer (2019) tested whether mock jurors exposed to negative pre-trial publicity are able to identify the influence the material had on their decision-making.

Prior to watching a video of a civil medical malpractice trial, mock jurors were exposed either to (a) prejudicial pretrial publicity (a news article that named the doctor defendant in the trial and discussed prior incidents of malpractice) or (b) a news article having nothing to do with the trial (about employers and preventative health maintenance).

A written voir dire was then conducted in which the mock jurors were given admonitions from a judge about the importance of being impartial and then were questioned about their ability to be fair and impartial. All mock jurors answered four questions:

After the voir dire, mock jurors watched the medical malpractice trial which included opening statements, expert testimony and closing arguments. Mock jurors then provided individual verdicts on negligence and awarded damages for pain and suffering if negligence was found.

As expected, exposure to prejudicial (to the defendant) pretrial publicity significantly increased plaintiff verdicts. Only 35% of the mock jurors reading the irrelevant article found the doctor liable while 52% of mock jurors exposed to the prejudicial pretrial publicity found the doctor liable. Damage awards for pain and suffering were significantly higher for mock jurors exposed to prejudicial pretrial publicity ($500,000) versus those not so exposed ($150,000).

Despite these stark effects of the prejudicial pretrial publicity on jurors' verdicts, very few mock jurors admitted during voir dire that the matreial had biased them: 87% of those exposed to the negative pretrial publicity said they would be able to view the evidence impartially, roughly the same as the 91% of jurors not exposed to the prejudicial pretrial publicity stating they could be fair and impartial.

When the 13% of mock jurors admitting bias from prejudicial pretrial publicity were removed from the "deciding" jurors, the liability and damages verdicts remain unchanged. The jurors admitting bias from pretrial publicity were no more nor less biased than the jurors denying bias from the pretrial publicity.

The researchers conclude that jurors are not able to assess accurately the impact that biasing pretrial publicity has on their decision-making. Voir dire fails to identify jurors biased by pretrial publicity. Juror bias, even when denied, can remain rampant when self-diagnosis is the basis of deciding impartiality.

Source Yokum, D., Robertson, C.T. & Palmer, M. (July 2019). The inability to self-diagnose bias. Arizona Legal Studies, Discussion Paper No. 12-35.