Using psychology to control law

Legal decision makers often fail to make use of relevant psychological research. In two areas, deceptive advertising and criminal sentencing, legal decision makershave welcomed social science research. In each, the research provided has been substantially flawed. Using a commercial that several courts evaluated for deception, I illustrate how the typical study that purports to measure deception produces results that are unnecessarily ambibuous. Then, based on research that looks closely at public responses to criminal cases, I show that the frequently cited survey measures of public preference reflect sentencing preferences for unrepresentative stereotypic criminal offenders. The weaknesses demonstated in these examples suggest that psychologists can present legal decision makers with a more accurate picture of human perceptions and preferences. If researchers present legal decision makers with informative research when the relevance of research is acknowledged, legal decision makers are likely to become more receptive and more knowledgeable when a new question warrants the application of social science evidence.An earlier version of this paper was delivered as the presidential address for Division 41, the American Psychology—Law Society, at the 1988 American Psychological Association meetings in Atlanta, Georgia.