Expert Evidence of "Risk Assessments" and the Preventive Detention of "Dangerous Prisoners"

The Dangerous Prisoners (Sexual Offenders) Act 2003 (Qld) provides for the preventive detention of a prisoner if there is "acceptable, cogent evidence" to a "high degree of probability" that the prisoner is a "serious danger to the community" because of an "unacceptable risk" that the prisoner will commit a "serious sexual offence". In preventive detention cases courts rely on the expert opinion of psychiatrists and psychologists who often use actuarial risk assessment instruments. In Black v Attorney-General (Qld) [2022] QCA 253 the Queensland Court of Appeal considered a decision to detain an offender who had a history of possessing and trading child sexual exploitation material but who had not previously been proved to have committed a contact offence against a child. This article analyses the reasoning of the Court of Appeal and critically examines the reliability of probabilistic risk assessment tools and the validity of expert evidence about risk in the preventive detention context.