In the United States, psychologists have appeared as expert witnesses at trials in which eyewitnesses evidence played a crucial role, a growing but controversial procedure. In Britain, legal precedents have precluded such testimony and psychologists have sought other, more indirect, methods of influencing law and practice. Examples are drawn from the author's own experience to show how research findings can indirectly influence the attitudes of the Judiciary, the general public and the police. The value of such confrontations between law and psychology are emphasized. Psychological research becomes more responsive, realistic and reliable while legal procedures and practices become more closely aligned with the cognitive capacities of the human observer. (Publisher abstract)