Implicit Bias and the Problem of Certainty in the Criminal Standard of Proof
Reynolds, Casey, Law and Psychology Review
The heightened standard of proof in criminal cases is crafted to allocate the risk of error to the state in order to protect the defendant from wrongful conviction. I reviewed empirical research to determine whether juries actually understand and follow this standard, and whether current attempts to define reasonable doubt adequately protect the defendant against a jurors' unconscious, or implicit bias. The research indicates that jurors have difficulty understanding the undefined reasonable doubt standard, and many current attempts at defining it. Further, current definitions are focused on the subjective doubt element, and few address the subjective certainty element, i.e. what types of inferences are proper in order for a juror to reach a subjective level of certainty. Research also indicates that various forms of implicit bias are widespread, difficult to identify, and could have a significant effect on verdicts. As a result, jurors are not instructed to be wary of their own implicit or explicit biases that may cause them to make improper inferences based on the evidence presented. An improved jury instruction on reasonable doubt would incorporate education about implicit bias and focus on the presumption of innocence, to prepare the jury to hear the evidence in an unbiased frame of mind. This instruction should be given as early in the proceeding as possible rather than at the end of the trial in order to reduce the risk of improper inferences based not only on the evidence, but on other aspects of the case such as the defendant and the nature of the charges.
Today, United States Supreme Court precedent requires that every element of a charge against a criminal defendant be proved "beyond a reasonable doubt" (BRD). (1) This mandate is drawn from the Due Process Clause and, when combined with case law on the Sixth Amendment, it has yielded a system where even sentence enhancement factors must be proven BRD to a jury. (2) In this way, the Court has changed the face of sentencing in the United States, underscoring the importance of this standard of proof in allocating the risk of error to the State in criminal cases. (3) Yet, despite the "axiomatic" (4) nature of the BRD concept, there is no requirement that it be explained to the jury at all, much less a consensus on how it should be explained. (5) Jurisdictions that have attempted to explain the standard to juries typically focus on subjective elements (i.e., what sort of doubt is sufficient for an acquittal), rather than giving any objective guideposts (i.e., what level of evidence is sufficient to meet the State's burden). (6) This lack of guidance, combined with a standard of review on appeal that is very deferential to the fact finder, yields a proof system in American criminal courts that does not live up to its reputation of giving a higher level of procedural due process to criminal versus civil defendants.
The stricter standard of proof in criminal cases is meant to allocate the risk of error to the State, thereby providing greater protection to the accused. (7) However, does the jury really understand their role in this process? Research on jurors' comprehension of reasonable doubt instructions suggests they do not--and further research on the impact of implicit bias on jurors' decision-making indicates failure to adequately explain this concept might make a real difference. (8) Most current explanations of the BRD standard focus on helping jurors probe their minds for a subjective level of doubt before settling on a conviction. (9) However, the definitions--when they are given at all--fail to warn jurors of the danger that they may have some pre-conceived notions about the defendant that help them reach a level of certainty about guilt, but do not constitute probative evidence. Examples abound--research suggests that whether jurors are conscious of it or not, they bring implicit bias to the courtroom on race, gender, economic status, and other factors based on their own individual experiences. …