The ability of mental health professionals (MHPs) to make accurate predictions of future violence has generated an enormous amount of research, theory, and debate since the early 1970s. Initially, most researchers were pessimistic about the ability of MHPs to predict violence. They based their view on a number of studies such as the one conducted by Kozol, Boucher, and Garofalo (1972), who found that predictions of future dangerousness, even if arrived at by a team of mental health experts, were highly inaccurate. In fact, Ennis and Litwack (1974) argued that MHPs have neither a special ability nor specialized training or techniques for making violence predictions. These authors concluded that the accuracy of MHPs' predictions is not much better than that of laypeople.
Additional research, commonly known as the “Baxstrom” (Steadman and Cocozza, 1974) and the “Dixon” (Thornberry and Jacoby, 1979) studies, supported the earlier results. The investigators found that psychiatric patients who were confined for years because of a finding of dangerousness turned out not to be dangerous at all when they were eventually released. As a consequence of these and similar findings, Monahan (1981) concluded that MHPs were wrong twice as often as they were correct in their violence predictions and that, accordingly, significant changes in public policy needed to be made. However, further scrutiny uncovered a number of methodological weaknesses in what Monahan (1984) referred to as the “first generation” of research and thinking on this topic. Monahan stressed the need for a second generation of research, thought, and policy on violence prediction rather than just conducting additional studies to demonstrate the inaccuracy of MHPs in predicting future violence among mentally disordered individuals. He proposed the need to (1) study various methods of prediction, (2) use actuarial techniques that incorporate clinical information, (3) employ