CCPR/C/115/D/2005/2010 (or the trial process and conviction in a particular case) would be incompatible with the humanitarian, rehabilitative and social objects and purposes of international transfer schemes. The party that stands to lose the most from non-cooperation in prisoner transfers is the prisoner, not the sending State. International prisoner transfer is not about transnational criminal cooperation; rather, it is a humanitarian and rehabilitative mechanism. (b) Claims under article 9 regarding unlawful and arbitrary detention in Australia State party’s observations 95. Australia refers to the author’s claims that, if his imprisonment in Australia constituted retroactive punishment under article 15 (1) of the Covenant, then his detention was unlawful and arbitrary and that the unlawfulness and arbitrariness flowed also from his procedurally unfair trial. Both grounds are without merit for the same reasons as those applicable to article 15 (1), i.e. that Australia did not assume full responsibility for the enforcement of the sentence. 96. Regarding the author’s argument that Australia could have followed the course of action taken by the United Kingdom in seeking the return of its nationals detained at Guantanamo Bay, the State party submits that there was no binding legal obligation on it, under the Covenant or otherwise, to adopt the approach taken by the United Kingdom. Author’s comments 97. The author rejects the arguments of Australia. He does not argue that his imprisonment was arbitrary or unlawful under Australian domestic law, but rather that it was arbitrary or unlawful under international law. 98. The author has never contended that Australia was legally required under the Covenant to request his return to Australia without trial. Nonetheless, it could have secured its humanitarian objective to return the author to Australia while simultaneously avoiding any cooperation in a prisoner transfer premised on retrospective punishment and an unfair trial. Further submissions from the parties 99. Australia rejects the author’s claim that the legality of detention under article 9 must not be assessed by reference to domestic law. Where the term “lawful” is used in various provisions of the Covenant, such as articles 9 (1), 17 (2), 18 (3) and 22 (2), it clearly refers to domestic law. Therefore, Australia maintains that the author’s detention in Australia was lawful under article 9 (1). 100. In his subsequent submission, in which the author informs the Committee about the decision of the United States Court of Military Commission Review in the case of David M. Hicks v. United States of America, the author submits that the decision necessarily renders his imprisonment for nine months in Australia unlawful and contrary to article 9. There was no lawful basis for the imprisonment in the absence of a valid conviction and sentence, upon which the transfer arrangement was based. (c) Claims under articles 2, 7, 14, 17 and 19 in connection with the plea agreement State party’s observations 101. The author founds these claims on two grounds. First, that Australia is responsible for breaches of the Covenant by acknowledging and adopting as its own the conduct of the United States in accepting the agreement. Second, that Australia is internationally 32