Experimental Interrogations: Tatbestandsdiagnostik, Objectivity, and the Impact of Experimental Psychology on Early-Twentieth-Century Criminal Justice

In 1904, Max Wertheimer and Julius Klein published a paper that shook the worlds of criminal justice and psychology. They proposed using psychological experiments, particularly word association tests, to assess whether criminal suspects had committed a particular crime. Over the following months and years, almost every German-language journal on psychology or criminal law, as well as many foreign-language journals, published something on this so-called Tatbestandsdiagnostik. Some hailed it as the "criminal investigation of the future." However, Tatbestandsdiagnostik's downfall was as swift as its rise to fame. By the advent of World War I, most psychologists and jurists had concluded that the association method was of no use in legal and police practice. This article traces the history of Tatbestandsdiagnostik as a case of how new forms of psychological knowledge circulated, were evaluated, and made an impact. It argues that proponents' insistence on the method's objectivity, its ambiguous relationship with psychoanalysis, and the possibility of demonstrating it to students and colleagues facilitated both its rapid rise and its demise.