Confession Evidence

Confession evidence is highly potent, and its incriminating effects are difficult to erase. This entry describes the impact of confessions on jury verdicts, examines three concerns about the way in which juries evaluate confession evidence, and considers the steps that can be taken to ensure that jurors assess such evidence appropriately.

In cases where a confession is disputed, a judge determines the voluntariness and admissibility of the confession during a preliminary hearing. In the American criminal justice system, if a confession is deemed voluntary, it is then submitted for consideration to the jury. In some states, the jury is specially instructed to make an independent judgment of voluntariness and to disregard statements found to be coerced; in other states, the jury receives no such instruction. Either way, it is clear that jurors faced with evidence of a confession, and the defendant's claim that it was false, must determine the credibility and weight of that evidence in reaching a verdict.

Mock jury studies have shown that confession evidence has a greater impact on jury decision making than other forms of human evidence, such as eyewitness identification and character testimony. Confessions are so difficult to overcome that mock jurors tend to trust them even when it is not legally and logically appropriate to do so. In a study that illustrates this point, Saul Kassin and his colleague presented mock jurors with one of three versions of a murder trial. In the [Page 137]low-pressure version, the defendant had confessed to the police immediately on questioning. In the high-pressure version, he was interrogated aggressively by a detective who waved his gun in a menacing manner at him. In the control version, there was no confession in evidence. Faced with the high-pressure confession, participants reasonably judged the statement to be involuntary and self-reported that it did not influence their decisions. Yet when it came to verdicts, this confession significantly boosted the conviction rate. This pattern appeared even in a situation in which subjects were specifically admonished by the judge to disregard confessions that they found to be coerced.

Criminal justice statistics reinforce the point that confessions tend to overwhelm other exculpatory evidence, resulting in a chain of negative legal consequences—from arrest through prosecution, conviction, and incarceration. Archival analyses of actual cases that contained confessions that were later proved false innocent have thus shown that when innocent confessors plead not guilty and proceed to trial, jury conviction rates range from 73% to 81%.

There are three bases for concern about the way in which juries can be expected to evaluate confession evidence in support of conviction. First, commonsense leads people to trust behaviors that do not appear to serve a person's self-interest, such as confessions. Most people believe that they would never confess to a crime that they did not commit and do not expect that others would either. Indeed, in a wide range of contexts, social psychologists have found that in perceiving the behaviors of others, people tend to overestimate the influence of dispositions and underestimate the influence of situational factors—a phenomenon known as fundamental attribution error.

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