Guardianship as a back-door insanity strategy: Parricide, antisocial personality disorder, and malingered psychosis in Brazil.

Intrafamilial homicide, particularly parricide, sits at a critical intersection of forensic psychiatry, criminal justice, and civil rights protection, and diagnostic labels generated in custodial settings may later shape high-stakes civil decisions. We report the case of a 24-year-old man imprisoned for parricide committed at age 19, who was referred to an independent forensic psychiatric evaluation within a Brazilian civil guardianship (curatela) action. The assessment integrated developmental and criminological reconstructions, collateral records (school and juvenile justice documentation, police and prison files), and a phenomenology-focused mental status examination with attention to secondary-gain contingencies. The longitudinal record supported early-onset conduct disorder, severe polysubstance use, instrumental violence, lack of remorse, and intact reality testing. Prison and telepsychiatry notes labeled the case "paranoid schizophrenia," but the reported psychotic symptoms were vague, internally inconsistent, and strategically framed, raising strong suspicion of malingering; there was no evidence of persistent delusions, formal thought disorder, negative symptoms, or psychosis-driven functional decline independent of substance use and antisocial behavior. The final formulation supported antisocial personality disorder with comorbid substance use disorder, without a chronic psychotic disorder, and preserved civil decision-making capacity. The opinion recommended against guardianship, highlighting how "psychiatrizing" antisocial conduct and importing thin prison diagnoses into civil proceedings can misdirect restrictions on rights and inadvertently function as a "back-door" route to penal reclassification. Rigorous, guideline-informed forensic reasoning is essential to distinguish psychosis from personality pathology and simulation.