CCPR/C/115/D/2005/2010 author, the allegations do not identify which instances of the provision of “material support or resources” are said to have been committed by him. Such failure made it difficult for the author to answer the charge against him. 9. In application of the International Transfer of Prisoners Act 1997 and subsequent amendment of 23 March 2004, Australia entered into a prisoner transfer arrangement with the United States, which recognized the author’s conviction and by which Australia agreed to imprison him in Australia to serve out the remainder of his sentence. Upon the transfer of a prisoner, the United States agrees to suspend its enforcement of the sentence and Australia agrees to respect and maintain the legal nature and duration of the sentence as determined by the United States. Australia assumes full responsibility for the enforcement of the sentence.2 10. By virtue of that arrangement, Australia participated directly in the retrospective punishment and imprisonment of the author, thus breaching article 15 (1) of the Covenant, according to which no one shall be held guilty of a retrospective criminal offence. The ordinary meaning of “held guilty” encompasses not only the moment of judgement and conviction before a criminal court, but also the enforcement of any sentence of punishment that follows from the conviction. Such interpretation is supported by the safeguards elsewhere in paragraph 1 concerning the application of penalties and in paragraph 2 concerning trial and punishment, which indicate that the scope of the protection extends to whatever punishment follows from a conviction. Furthermore, the protection of article 15 must extend to wherever enforcement of a sentence takes place, including where a sentence is enforced by another State in its own territory. Otherwise, one State would be free to enforce retroactive penalties imposed by another State’s courts without itself violating article 15. This would create an incentive to “contract out” the enforcement of sentences to other States whose imprisonment of an offender could not be challenged in the second State for retroactivity. Claims under article 9 regarding unlawful and arbitrary detention 11. The author’s detention at Guantanamo Bay was arbitrary because the United States failed to establish a justification for it under international law. It did not properly determine his status in accordance with international humanitarian law and did not charge him with a valid criminal offence. Furthermore, the absence of a lawful, non-retrospective conviction renders the detention arbitrary and unlawful. Its lawfulness is assessed not only according to domestic law but also according to international law. As for arbitrariness, detention flowing from a retrospective offence is a paradigmatic example of it, since it is premised on capricious, post facto government action. 12. The author’s trial was consequent to his designation as an alien unlawful enemy combatant under the Military Commissions Act by a Combatant Status Review Tribunal. If, as explained below, the process of the Combatant Status Review Tribunal was seriously flawed, there can be no certainty that he was eligible for trial under the Military Commissions Act. Moreover, if the Combatant Status Review Tribunal does not meet the requirement (in article 5 of the Geneva Convention relative to the Treatment of Prisoners of War (Third Geneva Convention)) of a “competent tribunal” for determining entitlement to prisoner of war status where a person’s status is in doubt (as it was in the author’s case) upon capture in an international armed conflict, then the author remained entitled to presumptive prisoner of war status until his status was properly determined by a competent 2 14 Under schedule 1, para. 9 (2), of the International Transfer of Prisoners Act, “the enforcement of the sentence in Australia is to be governed by the law of Australia and Australia alone is to be competent to take all appropriate decisions”.