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Cognitive Biases in Juror Decision-Making
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Cognitive Biases in Juror Decision-Making
Cognitive biases in juror decision-making have been identified as a core focal area in
legal psychology since it scrutinizes the way juror’s personal predetermine and stereotypes
impact the trial. Awareness of such prejudices is essential in order to prevent biases within the
legal processes, as the jurors also act based on their prejudices regardless of the proofs.
Hypothetical thinking, confirmation bias, and the halo effect are the operational and predictable
causes of how context and presentation of information give systematic and predictable causes of
how the mind produces errors according to the standard of rationality or sound judgment. Juror
decision is the decision that is arrived at by the juror in a particular legal trial; any trial process
should not entail such prejudices. This literature review shall examine the psychological aspect
of the biases above, research methods, the theoretical background of the research, and areas of
further study that will pave the way for a detailed investigation of the described facet of the
judicial system.
Interplay of Cognitive Biases in Juror Decision-Making
Cognitive bias influences the jurors in that it transforms the evidence into a particular
perception and adds discriminant value to them, leading to discriminatory verdicts. Previous
studies have shed light on different asymmetrical cognitive biases: confirmation bias, which
might imply that jurors tend to accept evidence that supports their prejudice, and the anchoring
effect, whereby the initial pieces of evidence are unduly determinative of the decision made.
Studies have also shown that these prejudices can predetermine jurors' decisions and are likely to
jeopardize jurors and lead to biased outcomes and wrong decisions. For example, Castrellon et
al. (2023) give an understanding of the relationship between social cognitive factors and
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prejudice of the juror's determination. They attribute the in-group bias concept that enables jurors
to disregard the outside group and support their group only.
Similarly, Curley et al. (2022) address verdict spotting and note that proof biases and
prior preferences shape the verdicts; the authors note that using the first piece of evidence
presented during the trial, jurors make their final decision. These observations align with Lewis
(2020), who unravels the phenomenon of wrongful convictions to point out that when juror
cognition breaks down because of behaviours such as the halo effect, the verdicts are wrong.
Altogether, it presents a rather bleak picture of juror decision-making as being pervasively
coloured by cognitive bias that can influence trials and verdicts, if not intentionally, then at least
subconsciously.
Current Research on Cognitive Biases in Juror Decision-Making
Current studies primarily focus on the goal of clarifying which specific prejudices impact
jurors' decisions and how these can be reduced. From the preceding studies, stereotyping and
prejudice have essential roles in jurors wherein other biases, including the personal
characteristics of the defendant or complex evidence in trials, may inundate. Korteling et al.
(2023) also state that cognitive biases are the reason behind unsustainable decision-making.
Although their work is not specific to sustainability, they write about jurors, and jurors are to
decide on the evidence and the testimonies where sustainable decision-making is applied. This
parallels the work of Baez et al. (2020), who focus on a legal perspective of biases in moral
judgments, having indicated that legal knowledge eliminates biases but not wholly.
On the basis of these findings, it can be concluded that although biases are an inherent
aspect of the human mind, they can be successfully managed, thus eliminating a number of
effects by means of juror education and appropriate adjustment of the methods of presenting the
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evidence. Collectively, these studies support the endurance of bias evidence in affecting jurors'
verdicts while demanding more investigations into the means of attenuating bias impact.
Methodological Approaches to Studying Juror Biases
The approaches used by the researchers to investigate juror biases also differ: Some even
recreate jurors' environments by using experimental-like techniques to mimic jurors' thinking
patterns. In contrast, others rely on post hoc examination of actual cases. Since there is a
variation in the approach of the studies, it becomes easier to understand various facets of how
biases affect the decisions made by jurors. Acciarini et al. (2021) synthesize a systematic
literature review to examine cognitive bias's business application and managerial decision-
making implications, including legal judgments. This broad approach allows for recognizing
cognitive biases in the context of at least the aggregate of studies, thus providing meta-analysis
insights into how these biases affect strategic decisions, including juror decisions.
Conversely, Azzopardi (2021) briefly discusses cognitive bias in the context of
information retrieval and considers how it can impact jurors regarding how information is
presented during trials. This means that the way evidence and testimonies are given is of utmost
significance and can influence the juror's decision-making. These different methodological
approaches provide depth to our knowledge about juror prejudices and the nature of the task to
control them: it is not a simple problem, and it takes more than a single approach to solve it. The
variety of methods used in the studies increases the confidence in the findings and opens up more
possibilities for eliminating potential juror biases in their decision-making.
Limitations
A systematic review of the literature on cognitive biases influencing juror decision-
making indicates various gaps, among them being sample size and heterogeneity. Some research
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exposes participants to artificial situations or uses university students as subjects that do not
necessarily represent the jury population. As much as the outcome can be used to make
predictions regarding actual court trials where jurors are chosen from different backgrounds and
experiences, it is a matter of debate. Moreover, this emphasis on Western samples, especially in
the US, limits the extrapolation of cultural biases affecting juror prejudice across the different
legal systems (Baez et al., 2020). Current techniques are mainly applied to identify biases
without emphasizing how to deal with them in real-time. Therefore, some studies suggest
educational approaches or procedural changes; however, empirical support is limited ( Castrellon
et al., 2023). There is a need for further research to establish the type of prejudice that jurors
have and the best ways to deal with it to acquire a fair trial and enhance the perceived legitimacy
of the justice delivery system.
Theory and Hypothesis
The theoretical background for the experiment conducted on jurors' cognitive biases is
developed on the foundation of the study by Loftus (1979), which exposed the influences of
eyewitness testimonies on jurors' decisions. This theory is even more applicable in this situation
because it recognizes that jurors have a particular set of cognitive susceptibilities, such as the
confirmation bias, brought about by the presence of an eyewitness that can make a juror either
for or against the defendant reaffirm that juror. Based on this, the hypothesis formulated is: The
participants are likely to convict the defendant if the eyewitness is not impeached or if the
eyewitness failed to appear in court to testify. This hypothesis will be tested using a multi-group
design with Eyewitness credibility as the independent variable and the juror's guilty verdict as
the dependent variable.
Variables
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The independent variable will be eyewitness testimony, which is defined as the testimony
of a witness in a court case. This variable will have three conditions: There are three types of
eyewitnesses: no eyewitness, unchallenged eyewitness, and discredited eyewitness. The
dependent variable will be the judgment of guilt, defined as the decision made by jurors about a
defendant's guilt. The operational definition of eyewitness testimony is no eyewitness, where
only the defendant is testifying; unrefuted eyewitness, where a witness testifies that he saw the
defendant committing the crime; and discredited eyewitness, where a witness testifies but is
crosschecked to indicate that there could be a flaw such as not wearing glasses. Operationally,
guilt judgment is defined as the verdict jurors give in response to these different conditions of
testimony.
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References
Acciarini, C., Brunetta, F., & Boccardelli, P. (2021). Cognitive biases and decision-making
strategies in times of change: a system
https://www.emerald.com/insight/content/doi/10.1108/MD-07-2019-1006/full/html
Baez, S., Patiño-Sáenz, M., Martínez-Cotrina, J., Aponte, D. M., Caicedo, J. C., Santamaría-
García, H., ... & Ibáñez, A. (2020). The impact of legal expertise on moral decision-
making biases. Humanities and Social Sciences Communications, 7(1), 1-12.
https://www.nature.com/articles/s41599-020-00595-8
Castrellon, J. J., Hakimi, S., Parelman, J. M., Yin, L., Law, J. R., Skene, J. A., ... & Carter, R. M.
(2023). Social cognitive processes explain bias in juror decisions.JSocial Cognitive and
Affective Neuroscience,J18(1), nsac057. https://osf.io/preprints/psyarxiv/v56wz
Curley, L. J., Murray, J., MacLean, R., Munro, J., Lages, M., Frumkin, L. A., ... & Brown, D.
(2022). Verdict spotting: investigating the effects of juror bias, evidence anchors and
verdict system in jurors. Psychiatry, Psychology and Law, 29(3), 323-344.
https://www.tandfonline.com/doi/full/10.1080/13218719.2021.1904450
Korteling, J. E., Paradies, G. L., & Sassen-van Meer, J. P. (2023). Cognitive bias and how to
improve sustainable decision making. Frontiers in Psychology, 14, 1129835.
https://www.frontiersin.org/journals/psychology/articles/10.3389/fpsyg.2023.1129835/
full
Lewis, D. N. S. (2020).JWrongful Conviction: Using Lived Experience to Explore Errors in
Juror CognitionJ(Doctoral dissertation, Walden University).
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https://www.proquest.com/openview/19001cce9d14275b8c5dd52fc8625ab1/1?pq-
origsite=gscholar&cbl=18750&diss=y
Azzopardi, L. (2021, March). Cognitive biases in search: a review and reflection of cognitive
biases in Information Retrieval. InJProceedings of the 2021 conference on human
information interaction and retrievalJ(pp. 27-37).
https://www.emerald.com/insight/content/doi/10.1108/MD-07-2019-1006/full/html
