The law is in some ways an obvious area where psychology could be of benefit. Many of the problems the law and legal procedures deal with are essentially psychological in nature. Law, like psychology, is fundamentally concerned with how people think, feel and behave; with the causes and modification of behaviour; and with the processes of perception, memory and decision theory. At the same time, law is a particularly difficult area for psychologists to tackle, not only for scientific, but also for ethical and political reasons. The role and functions of legal institutions such as juries and courts are by no means straightforward and the prima facie relevance of psychology can be deceptive. Moreover, even when psychology clearly has a relevant contribution to make, attempts to exert real influence on legal decisions or policy can be frustrating. A certain amount of scepticism on the part of lawyers is healthy. But the influence of psychology in legal contexts frequently has less to do with the quality of the psychology than with professional, political and organizational considerations.
Given the breadth of the field, this article is inevitably selective in the research and practice discussed. I shall not attempt to offer a comprehensive review of current work and its possible benefits. Rather, I aim to illustrate the range of topics, and the possibilities and difficulties in legal psychology using examples of recent research and attempts to influence legal decisions and legal policy. I first sketch briefly the growth of legal psychology.