Imprisonment and the Separation of Judicial Power: A Defence of a Categorical Immunity from Non-Criminal Detention

Abstract

The fundamental principle that no person may be deprived of liberty without criminal conviction has deteriorated. Despite a robust assertion of the principle by Brennan, Deane and Dawson JJ in Chu Kheng Lim v Minister for Immigration, subsequent jurisprudence has eroded it and revealed stark division amongst the Justices of the High Court. This article clarifies the contours of the disagreement and defends the proposition that, subject to a limited number of categorical exceptions, ch III of the Constitution permits the involuntary detention of a person in custody only as a consequential step in the adjudication of the criminal guilt of that person for past acts. This article proposes a methodology for creating new categories of permitted non-criminal detention and applies that methodology to test the constitutionality of the interim control orders considered in Thomas v Mowbray.