A. AND OTHERS v. THE UNITED KINGDOM JUDGMENT 55 Each applicant’s detention depended on his individual circumstances continuing to justify it, including the degree of threat to national security which he represented and the possibility to deport him to a safe country, and was subject to review every six months by SIAC. Each applicant was informed of the reason for the suspicion against him and given as much of the underlying evidence as possible and provided with as fair a procedure as possible to challenge the grounds for his detention. Moreover, SIAC was able to grant bail if necessary. The applicants were not, therefore, detained without hope of release: on the contrary there was the opportunity to apply for release together with mandatory review by the court to ensure that detention remained both lawful and proportionate in all the circumstances. It also remained open to the applicants to leave the United Kingdom, as the second and fourth applicants chose to do. 121. The applicants were judged to pose a serious threat to national security and were accordingly held in high security conditions, which were not inhuman or degrading. Each was provided with appropriate treatment for his physical and mental health problems and the individual circumstances of each applicant, including his mental health, were taken into account in determining where he should be held and whether he should be released on bail. A Special Unit was created at Woodhill Prison of which the applicants refused to make use (see paragraph 71 above). 122. To the extent that the applicants relied on their individual conditions of detention and their personal circumstances, they had not exhausted domestic remedies because they had not made any attempt to bring the necessary challenges. Any specific complaint about the conditions of detention could have been the subject of separate legal challenge. The prison authorities were subject to the requirements of the 1998 Act (see paragraph 94 above) and had an obligation under section 6(1) to act compatibly with the Article 3 rights of the applicants in their custody. In so far as the applicants’ complaints under Article 3 were based on the indeterminate nature of their detention, this was provided for by primary legislation (Part 4 of the 2001 Act), and Article 13 did not import the right to challenge in a domestic court a deliberate choice expressed by the legislature. B. The Court’s assessment 1. Admissibility 123. The Court observes that the second applicant was placed in detention under Part 4 of the 2001 Act on 19 December 2001 and that he was released on 22 December 2001, following his decision voluntarily to return to Morocco (see paragraph 35 above). Since he was, therefore, detained for only a few days and since there is no evidence that during that