Where an offender's psychotic episode is an aggravation of an underlying chronic psychotic disorder (paranoid schizophrenia) rather than a drug-induced psychosis alone, moral culpability may be reduced even though the episode was precipitated by voluntary substance abuse. The interrelationship between mental illness, non-compliance with medication, and substance use may make it impossible to disentangle causal factors, and the court should not simply attribute the offending to voluntary intoxication.
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