Tips to Reduce Confirmation Bias in Jurors, Attorneys, and Clients - Part 1 of 2

Steve Wood, Ph.D. & Bill Kanasky, Jr., Ph.D.

In November of 2022, Theranos’ founder and CEO, Elizabeth Holmes, was sentenced to 11.25 years in prison after being convicted on four fraud-related charges. According to Juror No. 6, Wayne Kaatz, the decision to convict was not easy because “It's tough to convict somebody, especially somebody so likable, with such a positive dream.”  The problem with this statement is that the question was not whether Elizabeth Holmes had a “positive dream;”[1] the question was whether she had broken the law. This type of response is not surprising from jurors, though. In civil and criminal litigation, jurors are instructed to come to an unbiased conclusion after impartially evaluating the evidence. However, despite their best intentions, this is not what occurs in jurors’ brains. A more likely scenario is:

•  Jurors come up with a hypothesis early in the trial;

•  They immediately begin seeking out case information to prove their hypothesis;

•  They give preferential treatment to evidence and testimony supporting their existing belief, while ignoring, discounting, or downplaying information that does not support it;

•  They tend to have better recollection of evidence and testimony supporting the side they favor; and

•  They entrench themselves deeply into their stance.[2] 

This process is commonly referred to as confirmation bias. Confirmation bias is the tendency for individuals to selectively search for, interpret, favor, and recall information that supports their pre-existing attitudes and beliefs, while also ignoring, criticizing, and downplaying information that conflicts with their attitudes and beliefs. At trial, confirmation bias can occur as early as jury selection and typically ends before jurors have heard closing arguments. Prior literature has even suggested that jurors tend to make up their minds after opening statements. [3] 

One of the primary reasons jurors make early, biased judgments is that all the information they receive is evaluated relative to their pre-established attitudes and beliefs. And pre-established attitudes and beliefs are difficult to change, even if they are wrong. This is why, despite widespread public service announcements, individuals still text and drive, drink and drive, and some refuse to get their COVID-19 vaccinations, etc. Likewise, just because attorneys present jurors with statistics and arguments the attorneys believe should resonate and make sense, jurors selectively ignore this information and make their own decisions, using the information they deem persuasive. It would be extremely rare for a juror to carefully weigh the evidence and make a purely rational, emotionless decision. 

So, how do you overcome jurors’ confirmation bias? One prevailing thought is to ensure that attorneys only select intelligent (e.g., educated, “book smart,” or able to comprehend complex information ) jurors because intelligence must be a safeguard against confirmation bias. There is a belief that less intelligent jurors cannot or will not make the cognitive effort to see both sides of the case, while more intelligent jurors can critically evaluate both sides and come to a reasonable, educated decision. Even though this argument may make intuitive sense, science does not support this assertion. Research has shown that there is very little correlation between intelligence and biased decision-making.[4]  The greater jurors’ cognitive capacity, the greater their ability to twist the case information, and the higher the number of arguments they can produce to support their preferred conclusion. 

Besides there not being a strong relationship between intelligence and confirmation bias, there is yet another reason why intelligent jurors may not be the solution. What if the juror is also angry at one of the parties? Prior research has shown that anger (relative to sadness or neutral mood) has been shown to lead to an increase in reliance on heuristics, or mental shortcuts, when processing information.[5]  In addition, high levels of anger can lead to “cognitive incapacitation” in which individuals can no longer think straight.[6]  This suggests that jurors in a state of anger are less focused on the quality of the arguments than individuals who are experiencing sadness or little emotion.  

Emotion does not always disrupt rational decision-making, however. Emotion and reason can occur in tandem. As Artz states, “Reasoning helps us to refine our emotions and emotions help us to evaluate and validate our reasoning.”[7]  There is also a concept known as “mood congruency” in which individuals process information that is congruent with the mood they are currently feeling. Individuals in a positive mood tend to perceive more positive information about a judgment target (e.g., defendant) and recall more positive information about that target. Conversely, individuals in a negative mood tend to perceive more negative information about a target and recall more negative information.[8]  Therefore, angry and intelligent jurors are the worst combination for both sides because they have the motivation and cognitive ability to convince other jurors. They can articulate their case points, and these will be the ones that they have selectively encoded and recalled to support their preferred conclusion. These intelligent jurors are also more likely to withstand counterarguments made by jurors who have selectively encoded the case evidence to reach an opposite conclusion. 

Some readers may be asking, “Are you saying to get less intelligent jurors?” No, we are not advocating that approach either. As we have already discussed, less intelligent jurors engage in the same biased information processing as more intelligent jurors. However, less intelligent jurors tend to remember fewer pieces of information than more intelligent jurors[9],  so they have difficulty articulating and defending their position during deliberations because they cannot back up their assertions with case evidence.   They may side with the plaintiff or the defendant, but when pressed to provide their reasoning, these jurors often respond, “I just feel like the plaintiff should get some money” or “I just feel like the defendant did nothing wrong.”

Continues in part 2 next week.


[1]Kay, G. (2022, January 5). Juror from Elizabeth Holmes trial says it was tough to convict the former Theranos CEO because she was 'so likable, with such a positive dream'. Business Insider. Retrieved from

[2] Kanasky, W. F. (n.d.). Juror confirmation bias: Powerful, perilous, preventable. Retrieved from

[3] Pyszczynski, T. & Wrightsman, L. (2006). The effects of opening statements on mock jurors' verdicts in a simulated criminal trial. Journal of Applied Social Psychology, 11, 301-313. 10.1111/j.1559-1816.1981.tb00826.x.

[4] Stanovich, K. E., West, R. F., & Toplak, M. E. (2013). Myside bias, rational thinking, and intelligence. Current Directions in Psychological Science, 22(4), 259-264.

[5]see Feigenson, N. (2010). Emotional influences on judgments of legal blame: How they happen, whether they should, and what to do about it. In B.H. Bornstein & R.L. Wiener (Eds.), Emotion and the law: Psychological perspectives (pp. 45–96). Springer.

[6]Goleman, D. (1995). Emotional intelligence: Why it can matter more than IQ. Scientific America, Inc.

[7] Artz, J. M. (2000). The role of emotion in reason: And its implications for computer ethics. ACM SIGCAS Computers and Society, 30(1), 14–16.

[8]see Feigenson, N. (2010). Emotional influences on judgments of legal blame: How they happen, whether they should, and what to do about it. In B.H. Bornstein & R.L. Wiener (Eds.), Emotion and the law: Psychological perspectives (pp. 45–96). Springer.

[9]Shipstead, Z., Harrison, T. L., & Engle, R. W. (2016). Working memory capacity and fluid intelligence: Maintenance and disengagement. Perspectives on Psychological Science, 11(6), 771-799.

Reptile Theory at Deposition: Extinct or Evolved?

Download Now

Stay updated: