Reducing the hindsight bias utilizing attorney closing arguments

Homicide inquiries

We recently had a homicide inquiry in our trust. The events around the release of the report made for a demoralising experience. The visible pain in the families of the victim and the perpetrator caused by the tragedy was heart-rending. As Medical Director, I also saw at first hand the powerful impact on the members of the team involved, my colleagues in general, the trust management and the health authority, all of whom strive to provide effective mental health services in one of the most deprived areas in the country. There were also political influences, especially the need to be seen not to tolerate poor performance. Allusions to disciplinary issues were not infrequent. We all found it very disturbing. I was forced to think a lot about homicide inquiries and became increasingly struck by a growing number of internal contradictions. I started making notes to help order my thoughts. I offer for discussion some conclusions using this inquiry (Scotland et al, 1998) as an example.

Hindsight Bias and Law

Abstract. Hindsight bias is the tendency to overestimate the foreseeability of an outcome once it is known. This bias has implications for decisions made within the legal system, ranging from judgments made during investigations to those in court proceedings. Legal decision makers should only consider what was known at the time an investigation was conducted or an offense was committed; however, they often review cases with full knowledge of a negative outcome, which can affect their judgments about what was knowable in the past. We conducted a systematic review of the literature on hindsight bias and law. We present five areas of law that hindsight bias affects (medical malpractice, forensic investigation, negligence, patent, criminal), two types of evidence that may lead to hindsight bias (visual and auditory evidence), and hindsight bias in experts and judges. Finally, we discuss strategies for reducing hindsight bias in legal decisions and recommend future research.

The Propensity Effect

The hindsight bias is an inability to disregard known outcome information when estimating earlier likelihoods of that outcome. The propensity effect, a reversal of this hindsight bias, is apparently unique to judgments involving momentum and trajectory (in which there is a strongly implied propensity toward a specific outcome). In the present study, the propensity effect occurred only in judgments involving dynamic stimuli (computer animations of traffic accidents vs. text descriptions), and only when foresight judgments were temporally near to (vs. far from) a focal outcome. This research was motivated by the applied question of whether the courtroom use of computer animation increases the hindsight bias in jurors' decision making; findings revealed that the hindsight bias was more than doubled when computer animations, rather than text-plus-diagram descriptions, were used. Therefore, in addition to providing theoretical insights of relevance to cognitive, perceptual, and social psychologists, these results have important legal implications.

Hindsight Bias

Hindsight bias occurs when people feel that they "knew it all along," that is, when they believe that an event is more predictable after it becomes known than it was before it became known. Hindsight bias embodies any combination of three aspects: memory distortion, beliefs about events' objective likelihoods, or subjective beliefs about one's own prediction abilities. Hindsight bias stems from (a) cognitive inputs (people selectively recall information consistent with what they now know to be true and engage in sensemaking to impose meaning on their own knowledge), (b) metacognitive inputs (the ease with which a past outcome is understood may be misattributed to its assumed prior likelihood), and (c) motivational inputs (people have a need to see the world as orderly and predictable and to avoid being blamed for problems). Consequences of hindsight bias include myopic attention to a single causal understanding of the past (to the neglect of other reasonable explanations) as well as general overconfidence in the certainty of one's judgments. New technologies for visualizing and understanding data sets may have the unintended consequence of heightening hindsight bias, but an intervention that encourages people to consider alternative causal explanations for a given outcome can reduce hindsight bias.

Shared Visual Attention Reduces Hindsight Bias

Hindsight bias is the tendency to retrospectively think of outcomes as being more foreseeable than they actually were. It is a robust judgment bias and is difficult to correct (or “debias”). In the experiments reported here, we used a visual paradigm in which performers decided whether blurred photos contained humans. Evaluators, who saw the photos unblurred and thus knew whether a human was present, estimated the proportion of participants who guessed whether a human was present. The evaluators exhibited visual hindsight bias in a way that matched earlier data from judgments of historical events surprisingly closely. Using eye tracking, we showed that a higher correlation between the gaze patterns of performers and evaluators (shared attention) is associated with lower hindsight bias. This association was validated by a causal method for debiasing: Showing the gaze patterns of the performers to the evaluators as they viewed the stimuli reduced the extent of hindsight bias.

The Influence of Liability Information, Severity of Injury, and Attitudes toward Vengeance on Damage Awards

This jury simulation study explored the effects of liability-related descriptive information, severity of injury, and attitudes toward vengeance on damage awards. 311 individual mock jurors read a trial summary describing a plaintiff injured in a motor vehicle accident. Half of the participants read liability-related descriptive information, theoretically unrelated to judgments concerning damages, and the other half did not. Half read about a mildly injured plaintiff, and the other half read about a severely injured plaintiff. In Phase 1 participants decided compensatory awards and in Phase 2 participants read punitive damages evidence and decided, if appropriate, punitive damages. The presence of liability-related description influenced neither compensatory nor punitive damages. Severity of the plaintiff's injuries affected compensatory awards and punitive awards. Although revenge has historically played an integral role in punitive damages, participants' attitudes toward vengeance were not associated with punitive damage awards.

Conduct and its consequences: attempts at debiasing jury judgments

Jurors in negligence cases are supposed to judge a defendant by the reasonableness of his or her conduct and not by the consequences of that conduct. But several studies have shown that a cognitive heuristic known as hindsight bias can skew post hoc judgments of some prior behavior. Thus, jurors who must evaluate the actions of a defendant may be influenced inappropriately by the consequences of those actions. A complementary problem arises when jurors must evaluate the injuries incurred by the plaintiff. Here, jurors' knowledge about the defendant's allegedly negligent conduct can proactively influence their assessment of the plaintiff's injuries and determination of damages. The purpose of the present study was to examine the effectiveness of two procedural techniques intended to reduce or eliminate the impact of hindsight bias in negligence cases--multiple admonitions from a judge about the proper use of evidence--and bifurcation (actually withholding irrelevant evidence from jurors). We presented a re-enacted automobile negligence trial to 355 jury-eligible adults drawn from the community, varied the evidence and instructions that they heard, and measured liability judgments and damage awards from individual jurors both before and after deliberating, and from juries. Results showed that admonitions were generally ineffective in guiding jurors to the proper use of evidence but that bifurcation was relatively more effective. Deliberations had no curative effect on jurors' misapplication of evidence.

Not the same old hindsight bias: outcome information distorts a broad range of retrospective judgments

The hindsight bias (e.g., Fischhoff, 1975) illustrates that outcome information can make people believe that they would have (or did) predict an outcome that they would not (or did not) actually predict. In two experiments, participants (N = 226) made a prediction immediately before receiving outcome information. Therefore, participants could not distort or misremember their predictions to make them align with the outcome information. In both experiments, participants distorted their reports of how certain they recalled having been in their prediction, how good of a basis they had for making the prediction, how long they took to make the prediction, and so forth. Experiment 2 showed that these effects were diminished when participants engaged in private thought about the upcoming questions prior to receiving outcome information, suggesting that the effect is not due to impression management concerns.