Implicit Racial Bias, the Zimmerman Trial, the Verdict


Discussion of the George Zimmerman verdict has been rampant in both the public and private spheres since jurors rendered the divisive decision in mid-July.  Zimmerman’s acquittal of all charges in the death of 17-year-old Trayvon Martin has sparked conversations on a plethora of sensitive topics, including Stand Your Ground laws, the current status of race relations in the United States, and what it means to live at the precarious identity intersection of being Black and male in a society that asserts itself to be “post-racial” despite ample evidence to the contrary.

Since the ruling, the concept of implicit bias has received newfound attention.  Implicit bias refers to the stereotypes or attitudes that affect our understanding, actions, and decisions in an unconscious manner.  The Kirwan Institute’s State of the Science: Implicit Bias Review highlighted the large body of compelling research on how these unconscious, automatically activated, and pervasive mental processes can be manifested across a variety of contexts yielding significant impacts.[1]  The increased dialogue around implicit bias and the Zimmerman verdict provides an opportunity to highlight research-based insights into how implicit bias may have played a role throughout the Zimmerman-Martin confrontation and during the subsequent trial.

Implicit association between blackness and criminality provides insights into the fateful confrontation

The stereotype of Blacks being criminal and violent has endured for many decades.[2]  Extensive research has documented how the media perpetuates this damaging association through its distorted portrayal of African American men that emphasizes negative connotations such as criminality, poverty, and unemployment.[3]  Recent research on implicit racial bias has only affirmed the persistence of this association.

One study asked participants to categorize items that appeared on a screen.  Some of the items were guns; others were handtools.  A human face flashed momentarily just before each object appeared on the screen.  These faces, either Black or White, appeared and vanished so quickly that participants did not consciously register their presence; however, the faces served as subliminal primes.  Researchers found that non-Black participants identified guns more quickly when they were primed with a Black face rather than White.[4]  Moreover, when a time constraint was added to the experiment, a Black face prime made participants more likely to misidentify a tool as a handgun versus when the prime was White.[5]  Because participants were unaware of these racial primes and simply believed they were sorting objects, these results speak to the presence and strength of the association between Blackness and criminality at an implicit level.

A 2004 study employed a similar priming technique to explore the association between Blackness and crime.  Researchers subliminally primed participants with either a Black male face, a White male face, or no face at all, and then presented subjects with degraded images that slowly gained clarity.  Some objects were crime-related (e.g., a gun or a knife) while others were innocuous (e.g., a camera or a pocket watch).  Participants were asked to indicate the exact moment when they were able to distinguish what the object coming into focus was.  Findings showed that the Black face primes considerably reduced the number of frames participants required to accurately detect crime-related objects, and this was true regardless of participants’ explicit racial attitudes.[6]  Thus, the strength of the association between Blackness and criminality was further established, as mere exposure to Black faces – even on a completely unconscious level – facilitated participants’ abilities to distinguish crime-related objects.

This implicit association between Blackness and criminality connects to current public discourse surrounding the Zimmerman trial and verdict.  Looking specifically at the Zimmerman-Martin confrontation in light of this implicit bias research, one scholar asserted that “race likely influenced Zimmerman’s perception that Martin posed a threat of criminality, whether Zimmerman was aware of this or not.”[7]  It seems reasonable that this association between Blackness and criminality was in Zimmerman’s mind – at least implicitly – that fateful night, particularly when his call to the Sanford police dispatcher about the “real suspicious guy” “who looks like he’s up to no good” was prefaced by his acknowledgement of the recent break-ins that had occurred in the community.

Research indicates that implicit biases among jurors affect deliberations

Once demographic details regarding the six individuals that comprised the Zimmerman jury were revealed, the composition of the jury provoked speculation and scrutiny.  All six were female, and all but one were White (the lone exception identified as Hispanic).  One question that arises from this is what role implicit bias may play in the context of a largely homogenous jury.  While the answer to this query is not completely clear, some research does suggest that lack of jury diversity can create an atmosphere in which implicit bias can surface, thereby affecting juror decisions.

For example, a 2006 study considered the group decision-making processes and outcomes of mock juries, finding that compared to homogenous all-White juries, diverse juries deliberated longer and considered a wider range of information, which could have an effect on verdicts rendered.[8]  Moreover, one influential figure who has weighed in on the significance of jury composition and the implicit biases jurors carry with them is former Supreme Court Justice Sandra Day O’Connor.  In her dissent in Georgia v. McCollum, she declared “[i]t is by now clear that conscious and unconscious racism can affect the way white jurors perceived minority defendants and the facts presented at their trials, perhaps determining the verdict of guilt or innocence … [M]inority representation on the jury may help to overcome such racial bias, for there is substantial reason to believe that the distorting influence of race is minimized on a racially mixed jury.”[9]

Applying these insights in the case of the Zimmerman jury, it is reasonable to consider that the decisions of this largely homogenous collective may have been influenced by their implicit biases, even if the jurors were completely unaware of the unconscious associations they brought with them to the deliberation room.

In addition, implicit biases can also shape how jurors recall evidence.  An experiment by law professor Justin Levinson investigated the role of implicit bias in how jurors recalled legal facts from a fictional case.  Participants served as mock jurors, were divided into three groups, and read the exact same story about a fistfight.  Across the three groups, though, the main character in the altercation varied; some read about William (a Caucasian), while the other two groups read about Tyronne (an African American) and Kawika (a Hawaiian), respectively.  When later asked to recall details of the confrontation, Levinson found that the mock jurors were significantly more likely to recall aggressive facts from the story when Tyronne was the main character as opposed to those who read about a Caucasian or a Hawaiian in that same role.[10]  Notably, Levinson found that the racially biased misremembering could not be attributed to the jurors’ explicit racial preferences; rather, the phenomenon he uncovered in this experiment points to the operation of implicit racial bias.  In ruling out explicit biases, Levinson showed how implicit racial biases can color jurors’ recollection of case details.

Connecting this research to the Zimmerman trial, the lack of witnesses made it difficult to establish exactly what responsibility either party bore in the initiation of the physical clash.  However, the idea from Levinson’s work that African Americans are significantly more likely to be recalled as aggressive than individuals of other races shows how implicit biases could have influenced the way in which Trayvon Martin’s role in the confrontation was recalled by jurors in their deliberations.

Other research on implicit bias among jurors found that jurors show less bias when a case is “racially charged” because they are more attentive to the role of race than they would be if the case did not have an explicit racial component.[11]  While assessing the extent to which race was a component of Zimmerman’s trial is a largely subjective endeavor, some signs indicate the race was largely overlooked.  Most notably, Juror B37’s recent interview with Anderson Cooper alludes to the fact that the jurors did not focus on the racial component of the trial when she stated, “I think all of us thought race did not play a role.  We never had that discussion.”[12]  By disregarding race on an explicit level, research would suggest that jury deliberations may have in turn become fertile ground for the proliferation implicit racial bias.

Implicit bias can shed light on how racial dynamics operate

As implicit racial bias continues to gain a foothold in public discourse, the real-world effects of this phenomenon will increasingly become a topic of interest, particularly in light of high-profile events such as the Zimmerman trial.  Although operating at an unconscious level, implicit biases should not be regarded as an excuse for behavior; rather, they are best viewed as powerful cognitive forces that contribute to individuals’ thoughts, behaviors, and decisions regardless of one’s explicit beliefs.  While it is nearly impossible to confirm the exact role(s) of implicit bias in the Zimmerman-Martin altercation and subsequent legal proceedings, understanding the research behind these unconscious mental processes sheds new light on how racial dynamics can operate, regardless of the presence or absence of outright racial animus.



[1] For more information on implicit racial bias and how it operates, see the Kirwan Institute’s State of the Science: Implicit Bias Review 2013, available at:

[2] Eberhardt, J. L., Goff, P. A., Purdie, V. J., & Davies, P. G. (2004). Seeing Black: Race, Crime, and Visual Processing. Journal of Personality and Social Psychology, 87(6), 876-893.

[3] Opportunity for Black Men and Boys: Public Opinion, Media Depictions, and Media Consumption. (2011). New York, NY: The Opportunity Agenda 

[4] Payne, B. K. (2001). Prejudice and Perception: The Role of Automatic and Controlled Processes in Misperceiving a Weapon. Journal of Personality and Social Psychology, 81(2), 181-192.

[5] Ibid.

 [6] Eberhardt, J. L., Goff, P. A., Purdie, V. J., & Davies, P. G. (2004). Seeing Black: Race, Crime, and Visual Processing. Journal of Personality and Social Psychology, 87(6), 876-893.

[7] Lee, C. (2013). Making Race Salient: Trayvon Martin and Implicit Bias in a Not Yet Post-Racial Society. North Carolina Law Review(91), 101-157.  p. 111 

[8] Sommers, S. R. (2006). On Racial Diversity and Group Decision Making: Identifying Multiple Effects of Racial Composition on Jury Deliberations. Journal of Personality and Social Psychology, 90(4), 597-612.

[9] Georgia v. McCollum, 505 42 (U.S. 1992).  p. 68.

[10] Levinson, J. D. (2007). Forgotten Racial Equality: Implicit Bias, Decisionmaking, and Misremembering. Duke Law Journal, 57(2), 345-424.

[11] Sommers, S. R., & Ellsworth, P. C. (2000). Race in the Courtroom: Perceptions of Guilt and Dispositional Attributions. Personality and Social Psychology Bulletin, 26(11), 1367-1379.Sommers, S. R., & Ellsworth, P. C. (2001). White Juror Bias: An Investigation of Prejudice Against Black Defendants in the American Courtroom. Psychology, Public Policy, and Law, 7(1), 201-229.

[12] Ford, D. (2013). Juror: ‘No Doubt’ that George Zimmerman Feared for His Life. CNN. Retrieved from

Cheryl joined the staff of the Kirwan Institute in October of 2007. Much of her current work focuses on implicit racial/ethnic bias. She is the author of the State of the Science: Implicit Bias Review, an extensive document that synthesizes a broad range of scholarly literature on how unconscious racial associations influence human decision-making and outcomes. The Implicit Bias Review highlights how cognitive forces that shape individual behavior without our awareness can contribute to societal inequities. Cheryl has also worked on a range of other projects, including alliance-building, intergroup relations, and racial profiling. She was a member of the research team that created Intergroup Resources, an online resource center that strengthens intergroup relations for social justice by sharing curricular materials, tools, and insights designed to facilitate bridge building across lines of difference. Cheryl is a graduate of the University of Dayton with a Bachelor of Arts in Sociology and Spanish. She completed a Masters of Arts degree in 2007 in the OSU Department of Sociology.