Retrospective mental health diagnoses of perpetrators are often circular reasoning

Evidence

There are other biases in our approach, some of which are common to studying victims or perpetrators of violent acts after the violence occurred. For example, many people exhibit mental health symptoms and are never formally diagnosed, and asking about mental health after a person has committed a violent act may be tautological. As described in a commentary on mass shootings: “‘Why did this man do this terrible thing?’ Because he is mentally ill. ‘And how do you know he is mentally ill?’ Because he did this terrible thing.” — Ryan Andrew Brown, Todd C. Helmus, Rajeev Ramchand, Alina I. Palimaru, Sarah Weilant, Ashley L. Rhoades, and Liisa Hiatt (RAND Corporation), Violent Extremism in America, 134

Categorization

• XREF: Relates to the general problem of retrospective inference in testimony, relevant against the reader’s goal of testing what actually changed extremists versus what they rationalize after the fact. — connects to: Instant post-9-11 blame explanations bypassed perpetrator psychology — Leonard S. Newman and Ralph Erber (eds.), Understanding Genocide: The Social…, 10; The mental-disorder theory of terrorism lacks reliable clinical evidence — John T. Jost and Jim Sidanius, Political Psychology, 4089; Personality inference risk circularity but can avoid tautology by split-sample reconstruction. (+2 more)
• SEED: Angle: the tautology trap in all post-hoc accounts of radicalization, where outcome itself becomes proof of cause.

Broader Connections

• The F Scale study’s coding allowed circular reasoning to creep into interpretations #exemplifies (0.88) — Martin Jay, The Dialectical Imagination, 744
• Personality inference risk circularity but can avoid tautology by split-sample reconstruction. #expands (0.85)
• The mental-disorder theory of terrorism lacks reliable clinical evidence #corroborates (0.75) — John T. Jost and Jim Sidanius, Political Psychology, 4089
• Popular psychology functions mainly to displace blame from evil actors onto prior causes #corroborates (0.75)