62 United Nations Convention Against Torture and its Optional Protocol thereafter breach his legal responsibility to intervene to prevent such activity’.230 A typical example of torture by acquiescence would be the outsourcing of interrogations to private contractors when the competent State officials know or should know that such private security companies might resort to torture practices. 130  The Committee in the meantime has very clearly outlined that States bear responsibility not only for the acts and omissions of their officials, but also for others, such as agents, private contractors, and others acting in official capacity or on behalf of the State, in conjunction with the State under its direction or control, or otherwise under colour of law.231 The Committee has also clarified that in case of privately run or owned detention centres, the staff is acting in official capacity and carrying out a State function, with State officials having the obligation to monitor as well as taking effective measures to prevent torture and ill-​treatment. The Committee has equally underlined that while the States parties’ obligations extend to all contexts of custody and control, this does not only include prisons, but also hospitals, schools, institutions taking care of children, aged, and mentally-​ill or disabled persons, military services and ‘other institutions as well as contexts where the failure of the State to intervene encourages and enhances the danger of privately inflicted harm’.232 131  As in other cases of State obligations to protect human rights against interference by private persons, the due diligence test as developed by the Inter-​American Court of Human Rights in cases of enforced disappearances might be applied.233 On the due diligence test, the Committee has stated, that if acts of torture or ill-​treatment are being committed by non-​State officials or private actors and State authorities or others acting in official capacity or under the colour of law know or have reasonable grounds to believe that these are taking place and they do not exercise due diligence to prevent, investigate, prosecute, and punish these non-​State officials or private actors in accordance with the Convention, the State as well as its officials will be responsible for the committed acts.234 The Committee has applied this principle to States parties’ not preventing and protecting victims from gender-​based violence, including rape, FGM, trafficking, and domestic violence. It thereby also reiterates that these practices may amount to torture.235 132  Thus, one may conclude that a State is responsible for acts or omissions of public officials and other persons acting in an official capacity, be it for directly committing, instigating, inciting, encouraging, acquiescing in, or otherwise participating or being complicit in torture. Especially from the acquiescence element, one may derive an important responsibility for States, when torture is committed by non-​State actors: States in such cases have to exercise due diligence to prevent, investigate, and punish such acts. Consequently, the Committee also emphasized that rape and violence committed by non-​State actors may equally amount to torture if the State fails to exercise due diligence to ‘intervene to stop, sanction and provide remedies to victims of torture’.236   US Reservation II.1.d to the Convention. See below Appendix A4. 232   CAT/​C/​GC/​2 (n 88) para  15.  ibid. 233   See the judgment Velásquez Rodriguez v Honduras, Series C No 4 (IACtHR 29 July 1988). 234   CAT/​C/​GC/​2 (n 88) para  18. 235  This is equally underlined in the Committee’s State Reporting procedure in relation to art 2:  see above Art 2. 236   CAT/​C/​GC/​2 (n 88) para 18; see also above 3.1.6.3. 230 231 Zach