Trial lawyers are keenly aware of how crucial a role that the composition of a jury plays in determining the outcome of a trial. In order for the legal process to successfully uphold the ideal of a defendants’ right to a fair trial, jurors must evaluate the evidence that informs the verdict in a fair and impartial manner. However, a considerable obstacle exists between the psychological reality of human cognition and the ethics of an equitable legal system. As much as we would like to believe that the immense responsibility of deciding someone’s legal fate would ensure that jurors remain objective and free of bias, this idealistic expectation conflicts with the psychological reality of decision-making. That is not a critique on the ethical constitution of jurors, but rather an acknowledgment that jurors are human beings and, just like all human beings, are prone to the self-deception that results from our hidden biases.

One of the most resilient and robust of these hidden biases is confirmation bias. In legal contexts, confirmation is particularly relevant as it can significantly influence jury selection and the overall fairness of the legal process. In this article we will lay the foundation for our deeper exploration of confirmation bias in jury selection and litigation, which will be covered in subsequent blog articles. By examining the psychological mechanisms behind confirmation bias and its potential influence on jury selection, we aim to shed light on the complexities of this cognitive bias within the context of the legal process.

Understanding Confirmation Bias

Confirmation bias refers to our inherent tendency to seek, interpret, and create information that verifies existing beliefs and opinions while disregarding or downplaying contradictory evidence. Confirmation bias is known as the “mother of biases” due its pervasive influence and the importance of counteracting it. This pervasiveness can be attributed to how easily, unintentionally, and without our awareness confirmation bias can fool us into thinking what we expect to see [1]. Confirmation bias explains why it often feels futile to argue politics with someone with a different viewpoint; you can construct the best argument in the world, and it won’t override a person’s drive to maintain their beliefs.

Confirmation bias may feel commonsensical when it comes to politics; it is easy to understand that beliefs that are a point of pride or identity or identity would be difficult to give up. What is more surprising is that people cling to their pre-existing views even when it is to their own detriment. What about a trial lawyer who relies on false stereotypes for jury selection, even after being presented with evidence that that approach has been shown to lead to inaccurate conclusions [2]. Accepting a scientifically validated approach to jury selection would benefit the trial lawyer by leading to improved trial outcomes, yet doing so would also mean upending their previous belief about what makes a good or bad juror. Once again, the drive to maintain your beliefs prevails. It seems it does not matter whether viewing things through the lens of your preconceptions leads to positive or negative outcomes for yourself, in either case people exhibit belief perseverance, clinging to their initial beliefs even after they have been discredited. 

Confirmation bias is not an individual criticism akin to calling someone stubborn or close-minded. Confirmation bias is the product of our brain’s efficiency-seeking mechanism that exists to cope with our limited cognitive capacity [3]. The resulting cognitive shortcuts, like confirmation bias, are useful adaptations, but can sometimes lead to errors in judgements. Confirmation bias is a fact of human nature, it is therefore not limited to a particular ideology or perspective; it affects individuals across diverse backgrounds and beliefs.

Confirmation Bias in Legal Settings

The legal system naturally places a high premium on unbiased decision-making, as it ensures fair and just trial outcomes. However, confirmation bias can subtly infiltrate jury selection and significantly impact the fairness of the trial process. The only way to overcome and compensate for confirmation bias, is to recognize the biases a person possesses and the situations in which confirmation bias is most likely to exert its influence. Only by addressing confirmation bias and adopting procedural safeguards can legal professionals effectively mitigate its more pernicious effects in order to enhance the objectivity and integrity of the legal system. 

Factors Influencing Confirmation Bias in Jury Selection:

  1. Pre-existing beliefs and attitudes of potential jurors: Individuals bring their personal biases and perceptions into any decision they make, including while serving as juror. These pre-existing beliefs can color their perception and evaluation of the evidence. Consider a juror who believes that people of higher socioeconomic status are more credible than people of low socioeconomic status. If you are a plaintiff attorney representing a person from a lower socioeconomic background against an affluent defendant, it would not matter if you presented evidence to challenge those expectations. Confirmation bias means that the juror’s expectations about your client’s credibility are going to overrule any evidence presented to the contrary.

For a demonstration of why this is the case, consider one study which asked participants to evaluate the academic potential of a 9-year-old girl named Hannah [4]. Participants were divided into two groups. Group 1 was told that Hannah was raised in an affluent community by college-educated parents both employed in professional settings. Group 2 was told that Hannah grew up in a run-down urban neighborhood and that her parents were uneducated blue-collar workers, creating low expectations. Unsurprisingly, the conditions presented to Group 1 created more positive expectations that led to higher evaluations of Hannah’s academic potential. What was surprising was how these evaluations were affected by the exact same evidence. Participants in each group were shown a video of Hannah taking an academic achievement test and doing about average; missing some easy questions but also getting some difficult questions correct. After viewing this evidence, Hannah received much lower evaluations from the participants who thought she was poor and much higher evaluations from the participants who thought she was rich. The same evidence was interpreted in the opposite direction depending on what the participants’ expectations were before seeing the evidence. 

This illustrates that virtually no type of evidence can easily penetrate confirmation bias. A person’s pre-existing beliefs will be verified by consistent evidence, unaffected by inconsistent, and fueled by mixed or ambiguous evidence. In any scenario, it is the pre-existing belief, not the evidence, that will impact the conclusion. 

  1. Media influence and pre-trial publicity: Media coverage can shape public opinion and influence potential jurors, potentially reinforcing existing biases. If a juror hears information about a trial prior to the case, the reporting will serve as a pre-existing belief that will distort the way they interpret any evidence or facts they are presented with at trial. Sensationalized media reporting or biased portrayals of defendants can sway jurors’ perceptions before they even set foot in a courtroom. It is important to note that it is no longer the case that high-profile cases are the only cases affected by pre-trial publicity. Whether the case was discussed on the news or not is only one avenue for exposure. Any person involved in a trial can be discussed on social media, and thus there are many more opportunities for a juror to be exposed to biasing information. Studies of mock jurors indicate that the effect of pre-trial publicity persists despite explicit instructions from a judge to disregard it [5]. If we assume people do not mindlessly consume pre-trial publicity but engage with case coverage and use that to formulate an opinion about a person’s guilt or innocence, then it is likely that jury deliberation will be impacted by confirmation bias. Confirmation bias, as we have seen, does not only occur with deeply held, personal beliefs, but even with more passingly acquired first impressions. But any belief, once acquired, is difficult to shake. If someone exposed to pre-trial publicity forms an opinion about who they think is guilty, that will serve as an initial belief that distorts the evaluation of any evidence they’re presented during a trial.
  1. Group dynamics within the jury: Once jurors are selected, they form a group that is characterized by features that render them particularly susceptible to maladaptive group dynamics (You can read more about why exactly that is in our previous article, “Avoiding Groupthink in the Jury Room”). The social pressure of group membership combined with a predisposition for confirmation bias creates a perfect environment for group polarization. In a jury deliberation, confirmation bias leads jurors to selectively attend to the people expressing views or opinions similar to theirs. When people discuss their similar views, group polarization can occur, in which those pre-existing views are reinforced by this agreement and then become amplified or more extreme as a result.  


Confirmation bias, with its selective attention and biased interpretation of information, poses a significant challenge within the context of jury selection. Understanding the psychological mechanisms behind confirmation bias allows us to recognize its potential influence on the legal system. By acknowledging and addressing these biases, we can strive for fairer and more impartial jury selection processes.

In the next article of this series, we will delve deeper into the impact of confirmation bias on jury decision-making. We will explore how confirmation bias can affect the evaluation of evidence and witness testimony, leading to potential distortions in the decision-making process. Stay tuned for the next installment as we continue to unravel the complexities of confirmation bias in the legal system.


  1. Gilovich, T., & Ross, L. (2016). The wisest one in the room: How you can benefit from social psychology’s most powerful insights. Simon and Schuster.
  2. Otis, C. C., Greathouse, S. M., Kennard, J. B., & Kovera, M. B. (2014). Hypothesis testing in attorney-conducted voir dire. Law and Human Behavior38(4), 392. 
  3. Dror, I. E. (2016). A hierarchy of expert performance. Journal of Applied Research in Memory and Cognition, 5(2), 121-127. 
  4. Darley, J. M., & Gross, P. H. (1983). A hypothesis-confirming bias in labeling effects. Journal of Personality and Social Psychology44(1), 20-33.
  5. Ruva, C. L., & Guenther, C. C. (2015). From the shadows into the light: How pretrial publicity and deliberation affect mock jurors’ decisions, impressions, and memory. Law and Human Behavior39(3), 294-310.