The paper focuses on a research project launched by Norwegian psychiatrists immediately following World War II. The project sought to investigate the roots of quislingism (collaboration with the Nazis) through psychiatric research on the collaborators. Considered with hindsight, however, the methodology of the project seems puzzlingly shallow. The paper discusses whether this was due to a general lack of adequate methodology in the contemporaneous sciences, or whether the explanation must be sought in the project's social and historical context. Ultimately, I conclude that considerable weight must be placed on the latter explanation, and that the general political ostracism of the collaborators in the postwar years played a major role in the psychiatrists' attitude.