Bill Cosby and Jury Bias: Can Jurors Recognize Their Own Biases?

Now more than ever, information is at our fingertips.  While the benefits of this are many, one potential downside has become apparent in the legal system.  The law assures defendants the right to an “impartial” jury.  However, the sheer amount of information available through the rapidly expanding use of technology means that jurors are increasingly likely to have prior knowledge about a case through media exposure.  In fact, in well publicized cases, one wonders how they can avoid knowing about it!

Ironically, even the media itself has noticed this.  In an article by NBC News, reporter Tracy Connor[1] discusses jury selection for the trial of Bill Cosby, a highly publicized case involving allegations of sexual assault against the famed comedian.  This trial perfectly illustrates the difficulties relating to media exposure and finding an unbiased jury, with its famous subject and expansive media coverage.  With the Cosby Trial as the context, Connor interviews Dr. Christopher Robertson, a legal scholar at the University of Arizona, who discusses a study[2] he conducted to determine: 1) whether jurors would be able to recognize their biases, and 2) whether they would self-select out of a jury by indicating those biases to the court.[3]  This article, described below, has interesting implications for jury selection and the potential consequences of pre-trial publicity on juror verdicts and damage awards.

Can Jurors Recognize Their Bias?

In this study, 174 individuals participated, and participants were randomly assigned to one of two groups.  In one group, participants were asked to read an article unrelated to the trial they would be witnessing.  The other group was asked to read an article that discussed the defendant in the case, a doctor accused of medical malpractice, including details of prior malpractice cases and settlements he had been involved in, along with other information that presented him in a negative light.

Regardless of which article they read, participants in both groups were then given written instructions from a mock judge emphasizing the need to be impartial.  Next, participants were asked if they could be impartial and base their decisions only on the evidence presented at the trial.  They were then asked to give a judgement about whether the doctor had committed medical malpractice, and, if they found the doctor liable, asked to provide a monetary figure for a damages award.

The results showed a difference in the verdicts rendered by the participants who read the neutral article in comparison to those who read the biased article.  Specifically, the percentage of participants who read the neutral article and found the doctor liable was significantly lower (35%) than the group who read the biased article (52%).  The noteworthy finding was that these numbers remained unchanged even when those who said they would be unable to consider the evidence fairly were removed from the analysis.  The average damage awards were also significantly higher for the group who read the biased article ($500,000) when compared to the group that read the neutral article ($150,000).

How Does Juror Bias Impact Voir Dire?

This study highlights the importance of thorough and detailed voir dire questioning of potential jurors to uncover bias.  If, as this study suggests, jurors are unable to recognize when information could impede their ability to fairly weigh the evidence in a case, it falls to the attorneys and their consultants to create questions that expose the biases of jurors of which even they are unaware.  To construct good questions, we need to think about what to ask jurors to make them comfortable admitting to bias, how to frame questions to make jurors more likely to admit to bias, and what to ask jurors to uncover unconscious biases.  Several previous blogs posts have addressed these issues, but some of our suggestions are summarized here.

1) Put Jurors at Ease

One important factor to consider is how to make jurors feel comfortable admitting their biases.  A juror who feels as though they will be judged negatively is likely to be reluctant to admit to any bias in public.  Try to soothe jurors’ worries by reassuring them that everyone has times when they cannot be fair, such as when asked to judge a competition where one of the participants is a friend or a relative.  Remind jurors that these biases don’t make them bad people, just not the best person to decide this particular case, given the possibility of biases that may impact their judgment.  Depending on what is permitted by the judge, you might provide a personal story of a time when you had difficulty being completely fair and impartial, which can help put jurors at ease and allow an open discussion about other times when the jurors have found themselves in similar positions.  Doing this normalizes biases and allows the jurors the safety of feeling as though they are members of a group rather than being singled out for admitting biases.

Further, reassure jurors that admitting to bias will not hurt you or your client’s feelings.  For the most part, jurors want to be polite, and they can be reluctant to say anything that feels like an attack on a specific individual or company.  This is why it is also important to keep your client (or client rep) out of the courtroom during the voir dire process.  Admitting bias is much more difficult when having to do so in front of the person you are biased against, so jurors are less likely to admit to having a bias against your case when your client is in the courtroom.

2) Structure Questions to Uncover Bias

Once the topic of bias has been introduced and jurors have been put at ease, now you can begin asking questions that seek to uncover a juror’s conscious and unconscious biases.  First, it helps to phrase questions so that jurors don’t feel singled out.  As mentioned above, jurors are much more comfortable being one among many, rather than the only one who has a bias.  Therefore, ask questions designed to imply that bias is normal and you expect many people to agree with your question.  For instance, rather than saying “Does anyone believe…,” use “How many of you believe…?”  The latter assumes some jurors will response, allowing those jurors the safety of a group while still revealing their bias to you.

Second, use questioning that implies degrees of bias rather than simple yes or no questions.  Jurors are more willing to admit that they might be somewhat biased than that they are completely biased.  Thus, in initial questions to the juror, it is more helpful to ask how difficult it would be for a juror to be fair, than to ask whether they are unable to be fair.  Given the negative implications around being “unable” to do something, jurors may shy away from admitting they may be biased.  Keep asking questions designed to normalize the bias and uncover degrees of bias, and eventually jurors’ biases may be exposed, even if they are never directly stated.  Once the juror takes the first step of admitting they may have difficulty being impartial, you are better equipped to get them to eventually admit they are unable to be completely impartial, thus securing the cause challenge.

3) Find Commonalities Between Your Case and the Jurors’ Experiences

Remember, jurors may not be aware of their biases, so in addition to asking questions that directly address bias, focus your questions on similarities between your case and the individual juror’s lives and their previous experiences.  The more common situations and experiences you find between the juror and your opponent, the more likely it is that the juror has developed a bias.  These detailed questions can allow you to determine whether there might be areas where jurors have unknown biases toward your case, allowing you to explore the issue further with that juror.  In some cases, the more you discuss the experiences and attitudes with the juror, the more they feel like a hypocrite when they say they can still be neutral (a phenomenon we psychologists call “cognitive dissonance”).  Ultimately, even if the juror never comes around to admitting the bias, you are nevertheless in a better position to exercise peremptory strikes.

For cases with extensive pre-trial publicity, we recommend asking the jurors – in a written questionnaire or at sidebar – to recall as much about what they have read or heard as possible, including how many times, the sources of the information, and whether they discussed it with others (as well as what was said in those discussions).  As with juror attitudes and experiences in general, the more the juror discusses what they know about the case or the parties involved, the more likely they are to recognize a potential bias.


In pursuit of an “impartial” jury, attorneys and consultants must be mindful of the impact of pre-trial publicity and that jurors are frequently unable to recognize when this type of information will affect their ability to fairly hear a case.  As the described study suggests, jurors’ self-evaluations alone are often inadequate, which can lead to significant impact on both verdict results and damage awards.  However, the construction of good voir dire questions can help uncover this bias and prevent unknowingly biased jurors from swaying the outcome of a case.  The wealth of information available to jurors today might make it difficult to find potential jurors who are unfamiliar with a case, but careful planning in voir dire can help prevent jurors whose views have been biased from being seated on a jury where they can cause the most damage.

By: Katy Cook, Ph.D. – Consultant

(With contributions from Christina Marinakis, J.D., Psy.D. – Director, Jury Research)


[1]  Connor, T. (2017, May 19). Cosby trial gears up with jury selection in Pennsylvania.  Retrieved from
[2]  Robertson, C. T., Yokum, D. V., & Palmer, M. J. (2013). The inability of jurors to self-diagnose bias. DOI:
[3]  This study has several limitations, some of which are acknowledged in the paper.