The National Institute of Justice guide for eyewitness identification evidence: Can it improve juror decision-making?

Mistaken eyewitness identifications of innocent lead to more false convictions in the United States than any other cause. In response to concerns about the reliability of eyewitness evidence, the National Institute of Justice (NIJ) in 1999 published a Guide for the gathering and preservation of eyewitness evidence by law enforcement personnel. Previous research has shown that eyewitness identifications are more accurate when obtained using procedures recommended in the NIJ Guide. This experiment assessed whether informing jurors about the Guide can improve their ability to discriminate between eyewitness identifications likely to be accurate and those likely to be inaccurate and, if so, how to most effectively provide jurors with such information. ^ Seven hundred sixteen U.S. citizens who reported for criminal jury duty participated. Half of the participant jurors read a summary of an armed robbery trial in which the police followed the NIJ Guide when obtaining an eyewitness identification of the defendant. The other half read about an identical case in which the police did not follow the Guide. Jurors received information about the Guide from a court-appointed expert witness, one of the attorneys in the case, the trial judge, the judge in combination with one of the attorneys, or from no one (in the control groups). Jurors then rendered a verdict in the case and answered questions about the evidence in the case. ^ When an expert witness or the judge (either alone or in combination with one of the attorneys) informed jurors about the Guide, the jurors voted to convict defendants likely to be guilty and to acquit defendants likely to be innocent more often than did uninformed jurors assigned to a control group. These data suggest that informing jurors about the NIJ Guide using expert testimony or instructions from a judge will improve the quality and accuracy of jurors' verdict decisions in cases involving eyewitness identification evidence. However, more research is needed to determine whether the judge will remain an effective source of information about the Guide in a longer, more detailed trial scenario and to learn more about the underlying psychological processes governing the effects observed in this experiment. ^

Age differences and conformity in juror decision -making

The purpose of this experiment was to investigate whether older adults conform more than young and middle-aged adults on a juror decision making task. Degree of group pressure, personality characteristics, gender, and social influence processes were also examined.^ Registered voters (208 participants) completed a personality questionnaire. Several weeks later, groups of six participants listened to a robbery case that portrayed the defendant as guilty. Afterwards, participants completed the first of two ballots. On the first, participants rated the defendant's degree of guilt and scored their degree of certainty in this verdict rating. They also indicated in writing which piece of information (a statement of evidence) from the robbery case supported their verdict ratings. Next, participants reviewed photocopies of five contrived first ballots. Then participants completed second ballots, in which they again rated the defendant's degree of guilt and scored their degree of certainty in this verdict rating. Finally, participants rated the importance of the five contrived first ballot verdict ratings (normative social influence) and statements of evidence (informational social influence) in reaching their second ballot verdict ratings.^ The results demonstrated that not only did older adults conform as expected, but all age groups conformed; that is, all age groups changed their verdict ratings. After reviewing the other jurors' contrived first ballots (group pressure), participants rated the defendant as less guilty on their second ballot than on their first. However, only older adults significantly changed their level of certainty in their verdict ratings from first to second ballot compared to young and middle-aged adults. With regard to personality characteristics, only rigidity predicted conformity in young and middle-aged adults but not in older adults. It was also found that females conformed more than males. Finally, all three age groups reported that different social influence processes (normative vs. informational) were important in reaching their second ballot verdict ratings. The results of this research indicate that various factors can influence young, middle-aged, and older adults as they reach verdicts. Knowledge of these factors may help alter stereotypes of older adults in terms of conformity, rigidity, and desirability as jurors. ^

Effects of alcohol intoxication and encoding conditions on eyewitness memory

Several researchers have investigated the effects of alcohol on memory. Few researchers have studied the effects of alcohol on an eyewitness's recall and recognition of crime events. This study proposed to examine the effects of alcohol and viewing conditions on subjects' ability to recall information regarding a videotaped bank robbery. Thirty male and 22 female subjects participated in a 2 (consumption: alcohol v. no alcohol) x 2 (lighting: good v. poor) factorial experiment with Average Accuracy and Total Amount of Information recalled as the primary dependent measures. There was no significant difference between the Intoxicated and Sober subjects regarding the amount of information recalled or their average accuracy. The main effect for lighting conditions and gender differences were also not significant.