Context effects in forensic science: a review and application of the science of science to crime laboratory practice in the United States.

This article discusses the phenomenon of "context effects" by reviewing the findings and practices of a range of scientific fields, including astronomy, physics, biology, medicine, and especially the relevant research and theory from psychology. Context information, such as expectations about what one is supposed to see or conclude, has been found to have a small but relentless impact on human perception, judgment, and decision-making. The article then considers the vulnerability of forensic science practice to context effects, and concludes by suggesting that forensic science adopt practices familiar in other fields of scientific work, in particular blind or double-blind testing and also the use of evidence line-ups.

The impact of jury instructions on the fusion of liability and compensatory damages.

This study examined whether special jury instructions or the bifurcation of liability and compensation decisions would counter the tendency for evidence concerning the defendant's liability to affect damages awards. Mock jurors made liability and award decisions in response to a case description in which the level of defendant responsibility for the plaintiff's injuries and the type or timing of damages instructions were systematically varied. Instructions not to discount awards for uncertainty about the defendant's fault and instructions not to increase awards to punish the defendant's carelessness reduced the impact of the defendant's conduct on awards, while bifurcation did not. Additional findings suggest, at least in the context of the present study, that discounting may be a somewhat more potent process than surcharging. Possible explanations for these effects are discussed.

The application of signal detection theory to decision-making in forensic science.

Signal Detection Theory (SDT) has come to be used in a wide variety of fields where noise and imperfect signals present challenges to the task of separating hits and correct rejections from misses and false alarms. The application of SDT helps illuminate and improve the quality of decision-making in those fields in a number of ways. The present article is designed to make SDT more accessible to forensic scientists by: (a) explaining what SDT is and how it works, (b) explicating the potential usefulness of SDT to forensic science, (c) illustrating SDT analysis using forensic science data, and (d) suggesting ways to gain the benefits of SDT analyses in the course of carrying out existing programs of quality assessment and other research on forensic science examinations.

Explaining "pain and suffering" awards: the role of injury characteristics and fault attributions.

The present research explored factors thought to affect compensatory awards for non-economic harm ("pain and suffering") in personal injury cases. Experiment 1 showed that the nature and severity of the plaintiff's injury had a strong effect on perceptions of the extent of harm suffered and on award amounts. The parties' relatively active or passive roles in causing the injury affected assessments of their degree of fault, but perceived fault had little influence on awards. Experiment 2 replicated with more varied cases the strong impact of injury severity on harm perception and on awards for pain and suffering. In both studies, the disability and the mental suffering associated with injuries were stronger predictors of awards than were pain and disfigurement.