The critical factor in determining whether drug-induced psychosis mitigates or aggravates sentence is the offender's degree of foreknowledge of the probable consequences of drug ingestion. Where the offender knew or ought to have known that drug-taking was likely to produce psychosis and dangerous behaviour, the self-induced psychosis is an aggravating factor. However, drug-induced psychosis may be mitigatory where the offender had no awareness that the drug might trigger psychosis, or where psychosis occurs during withdrawal. The concept of 'reckless intoxication' developed in the alcohol context applies equally to drug-induced psychosis.
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