Kable v Director of Public Prosecutions (NSW)

The Parliament of New South Wales passed the Community Protection Act 1994.[2] It authorised the Supreme Court of New South Wales to make an order requiring that a single individual could be detained in prison if the Court was satisfied that that person posed a significant danger to the public. The Act was later amended to authorise the Court to detain a single named person, Gregory Kable, who was sentenced to five years imprisonment for the manslaughter of his wife.[3]

The legislation was closely modelled on a law passed in Victoria, the Community Protection Act 1990, which was enacted to authorise 'preventive detention' for Garry David.[4]

In gaol, Kable had sent threatening letters to the people who denied him access to his children. He was charged and sentenced to an additional 16 months for writing the letters in 1990. Four years later, having been granted no parole, he was released from gaol. His release coincided with a state election campaign which featured "law and order" as a major issue. Legislation was subsequently passed through parliament naming him explicitly.

In early 1995, Justice Levine of the Supreme Court made an order under the Community Protection Act, in respect of him, requiring that Kable be detained for a period of six months. He appealed that decision, and his appeal was dismissed by the NSW Court of Appeal.[5] It was from that decision that the appeal was brought to the High Court, on grounds of constitutional invalidity.

He was represented by Sir Maurice Byers, a former Solicitor-General of Australia.[6]

The argument which eventually persuaded a majority of the members of the High Court was the argument that:

"the Act vests in the Supreme Court of New South Wales a non-judicial power which is offensive to Chapter III of the Constitution. Hence any exercise of that power would be unconstitutional and the Act conferring the power would be invalid. ... The argument is not one which relies upon the alleged separation of legislative and judicial functions under the Constitution of New South Wales. Rather it is that the jurisdiction exercised under the Act is inconsistent with Ch III of the Commonwealth Constitution because the very nature of the jurisdiction is incompatible with the exercise of judicial power."

The High Court held that the law was unconstitutional, and in the process construed a limitation on the powers of state courts vested with federal jurisdiction under Chapter III of the Constitution. They held that Chapter III, particularly section 71 purports to vest federal judicial power in the Supreme Court of New South Wales. The Act vested in the Supreme Court powers that were incompatible with the exercise of judicial power of the Commonwealth, that is, the law required the Supreme Court to exercise a power incompatible with its role in the federal judiciary.[7]

Subsequently, Mr Kable sought an award of damages for abuse of process, false imprisonment and malicious prosecution. His application was dismissed by the Supreme Court of NSW,[8] but he was successful in an appeal to the NSW Court of Appeal on his claim of false imprisonment with damages to be assessed.[9] The State of NSW then appealed to the High Court.[10]

The High Court unanimously upheld the appeal and dismissed Mr Kable's claims, holding that a detention order made by a judge of the Supreme Court of NSW was valid until it was set aside and provided lawful authority for Mr Kable's detention.[11][12]

• Australian constitutional law

• Winterton, G. et al. Australian federal constitutional law: commentary and materials, 1999. LBC Information Services, Sydney.

• Community Protection Act 1994
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