A/56/156 23. When detained, members of sexual minorities are often considered as a sub-category of prisoners and detained in worse conditions of detention than the larger prison population. The Special Rapporteur has received information according to which members of sexual minorities in detention have been subjected to considerable violence, especially sexual assault and rape, by fellow inmates and, at times, by prison guards. Prison guards are also said to fail to take reasonable measures to abate the risk of violence by fellow inmates or even to have encouraged sexual violence, by identifying members of sexual minorities to fellow inmates for that express purpose. Prison guards are believed to use threats of transfer to main detention areas, where members of sexual minorities would be at high risk of sexual attack by other inmates. In particular, transsexual and transgendered persons, especially male-to-female transsexual inmates, are said to be at great risk of physical and sexual abuse by prison guards and fellow prisoners if placed within the general prison population in men’s prisons. 24. The Special Rapporteur has received information according to which members of sexual minorities have been subject to cruel, inhuman or degrading treatment in non-penal institutions. In a number of countries, members of sexual minorities are said to have been involuntarily confined to state medical institutions, where they were allegedly subjected to forced treatment on grounds of their sexual orientation or gender identity, including electric shock therapy and other “aversion therapy”, reportedly causing psychological and physical harm. The Special Rapporteur notes, in particular, that the World Health Organization removed homosexuality from its International Classification of Diseases-10 (ICD-10) in 1992. The Special Rapporteur has received information according to which, in a number of countries, persons suspected of homosexuality have been subjected to compulsory, intrusive and degrading medical examinations of anus and penis in order to determine whether penetration had taken place, inter alia, within the context of enlistment for military service. 25. Finally, the Special Rapporteur notes and shares the views of the Special Representative of the Secretary-General on human rights defenders regarding “greater risks ... faced by defenders of the rights of certain groups as their work challenges social structures, traditional practices and interpretation of religious precepts that may have been used over long periods of time to condone and justify violation of the human rights of members of such groups. Of special importance will be ... human rights groups and those who are active on issues of sexuality, especially sexual orientation ... These groups are often very vulnerable to prejudice, to marginalization and to public repudiation, not only by State forces but other social actors.”16 D. Torture and impunity 26. The Special Rapporteur has noted in the past that the single most important factor in the proliferation and continuation of torture is the persistence of impunity, be it of a de jure or de facto nature. Causes of impunity of a de jure nature encompass measures relieving perpetrators of torture of legal liability, inter alia, by providing an unrealistically short period of prescription, adopting acts of impunity or by granting amnesties to perpetrators of grave violations of human rights. It is with regard to the granting of amnesties that the Special Rapporteur wishes to review the recent developments in international law on the question of the compatibility of amnesties with States’ international obligations to combat torture. 27. The Special Rapporteur would like to draw Governments’ attention to the Vienna Declaration and Programme of Action, which stipulates that “States should abrogate legislation leading to impunity for those responsible for grave violations of human rights such as torture and prosecute such violations, thereby providing a firm basis for the rule of law”.17 The Special Rapporteur further notes the report “Question of the impunity of perpetrators of human rights violations (civil and political)”, prepared by Mr. Louis Joinet of the Subcommission on Prevention of Discrimination and Protection of Minorities, pursuant to Subcommission decision 1996/119, which states that “amnesty cannot be accorded to perpetrators of violations before the victims have obtained justice by means of an effective remedy” and that “the right to justice entails obligations for the State: to investigate violations, to prosecute the perpetrators and, if their guilt is established, to punish them”.18 As requested by the Subcommission in its decision 1996/119, Mr. Joinet drafted a set of principles for the protection and promotion of human rights through action to combat impunity,19 in which he states that “there can be no just and lasting reconciliation unless the need for justice is effectively justified” and that “national and 7