A/HRC/37/50 including in off-shore processing centres. Depending on the context, problems may range from extreme overcrowding to prolonged solitary confinement, and from insufficient access to food, water and medical care to deliberate abuse by State officials, private guards, or fellow detainees, including torture and ill-treatment, systematic extortion, sexual abuse, and even enslavement. Even torture and ill-treatment of migrant children has been reported to be widespread, ranging from various forms of sexual abuse to being "tied up, gagged, beaten with sticks, burned with cigarettes, given electric shocks, and placed in solitary confinement, causing severe anxiety and mental harm".29 20. It is clear that any detention regime which, as a matter of deliberate policy or as a consequence of negligence, complacency or impunity, subjects or exposes migrants to treatment or conditions of detention grossly inconsistent with universally recognized standards, most notably the "Nelson Mandela Rules",30 is incompatible with the prohibition of torture and ill-treatment,31 regardless of economic or budgetary considerations.32 As a general rule, the threshold of prohibited ill-treatment will be reached sooner with regard to migrants with an irregular status or with other vulnerabilities.33 Moreover, ill-treatment or grossly inadequate detention conditions can even amount to torture if they are intentionally imposed, encouraged or tolerated by States for reasons based on discrimination of any kind,34 including based on immigration status,35 or for the purpose of deterring, intimidating, or punishing migrants or their families, coercing them into withdrawing their requests for asylum, subsidiary protection or other stay, agreeing to "voluntary" return, providing information or fingerprints, or with a view to extorting money or sexual acts from them. 3. Prolonged or indefinite detention 21. Great concern also arises with regard to the use of procedures that are of a nature or deliberate design to render migrant detention potentially indefinite, to maximize uncertainty, unpredictability and frustration, or to prompt affected migrants to withdraw their requests for asylum, subsidiary protection or other stay and agree to "voluntary" return in exchange for their release. Where migrants are held under a regime of administrative detention outside the criminal justice system, they often do not benefit from essential procedural safeguards such as access to an interpreter and to legal counsel and the right to an effective legal remedy and periodic review. As a result, such migrants are often deliberately kept in a legal "limbo" with no realistic prospect of release or alternative measures, and no practical means of influencing the process and its duration. In other contexts, where unauthorized entry is criminalized, pretrial detention often is automatically imposed until the conclusion of legal proceedings, which in practice regularly leads to prolonged if not indefinite detention. In both cases, where migrants are accompanied by family members, they are often detained separately from their spouses and even their children, generally on the pretext of administrative regulations, with the withdrawal of their requests for asylum, subsidiary protection or other stay and their "voluntary" return being the only realistic prospect of release and family reunification. Also, in many contexts throughout the world, migrant children are being routinely detained, both individually and together with their families. A particularly traumatic form of migrationrelated detention combining these elements is long-term offshore-confinement on isolated islands or extra-territorial enclaves. 29 30 31 32 33 34 35 A/HRC/28/68(05.03.2015), §60. A/RES/70/175 (17.12.2015), particularly Rule 43(1). ECtHR, MSS_v._Belgium_and_Greece(No.30696/09), Jgmt 21.01.2011, §233; ECtHR, Kalashnikov_v._Russia (No.47095/99), Jgmt_15.07.2002), §102; CCPR, Mukong_v._Cameroon, No.458/1991(21.07.1994), §9.4; IACtHR, Suárez Rosero_v._Ecuador, Jgmt,_12.11.1997,_§91; IACtHR, Montero-Aranguren_et_al_v._Venezuela (05.07.2006), §91; UNSRT(van Boven), Annual Report (e/cn.4/2004/56), 23.12.2003, §49. CCPR, Mukong_v._Cameroon, No.458/1991(21.07.1994), §9.3. ECtHR, Tarakhel_v._Switzerland_(29217/12), Jgmt_04.11.2014, §§118-119. Art.1 UNCAT. ECtHR, Hode_and_Abdi_v._UK_(No.22341/09),_06.11.2012, §56. 7