The first edition of Psychology and Law was published in spring 1998. Much of the text was written in 1995–6, and the last eight years have seen a number of important developments in research and practice in most of the areas covered in the book. The volume of new research in the psychology and law area is reflected in the launch of several new journals, including the British Psychological Society's Legal and Criminological Psychology and the International Journal of Police Science and Management. This book is based on a detailed analysis of the published research literature as well as on material published in scientific reports, on conference proceedings and on data gathered during the course of our own recent research projects. Not only is our review exhaustive, but it is also up to date so that students and researchers can have access to the latest developments in the field. Our text is directed at students and researchers interested in the forensic issues to do with gathering evidence. We present the experimental and theoretical detail that is required for scientists to be able to evaluate the research and disseminate the findings to relevant professionals.
The emphasis of the current text, like the earlier edition, is on the perceived credibility of participants in the criminal justice system (be they witnesses, suspects or victims) and factors that influence the accuracy of evidence. Chapter 2, for example, examines the nonverbal characteristics and physiological correlates of deception. Chapter 3 reviews work on criminal appearance stereotyping. Throughout the text, there is an emphasis on the usefulness of the research. Thus, in Chapter 3, we ask whether research on stereotyping may help us understand why certain people (such as innocent suspects) may be chosen more often from line-ups than other people, and why the facial appearance of defendants can influence judicial decision making. We also examine how research has influenced practice. For example, Chapter 5 surveys psychology's major contributions to improving the ways that witnesses should be interviewed. The major focus is on children and other vulnerable witnesses (such as adults with learning disabilities). The way that the results from many research studies from several different countries cohere into a set of guidelines (such as those published by the Home Office) is described.
In addition to illustrating the practical relevance of research in the psychology and law area, our text examines the strengths and weaknesses of research methods that have been used to collect data in the laboratory and the field. For example, in Chapter 8, we critically evaluate studies that have used the mockjury paradigm. Chapter 6 assesses research on factors influencing the quality of witness evidence, and Chapter 9 considers the extent to which there is a