Duty to prosecute or extradite 24. Those who violate the prohibition on torture must be held responsible. 318 Those responsible may include those within the institution in which the detainee was held who knew or ought to have known that the torture or ill treatment was taking place and who failed to prevent it or report it. 25. Article 5 of the UNCAT requires states to ‘take such measure as may be necessary to establish jurisdiction over such offences in cases where the alleged offender is present in any territory under its jurisdiction’, or to extradite them to another state. Duty to protect from acts of private actors 26. The prohibition in the ICCPR and in the other instruments does not just relate to whether the act was carried out but a public official, but there is also a duty on the state to protect against acts committed by private actors.319 This may arise in a number of circumstances:  Where groups or persons exercise de facto government or state authority. 320  Where the state failed to respond to acts of private individuals and therefore ‘acquiesced’.321  ‘where State authorities…know or have reasonable grounds to believe that actors of torture or ill-treatment are being committed by non-State officials or private actors and they fail to exercise due diligence to prevent, investigate, prosecute and punish…the State bears responsibility’. 322 Duty to provide effective remedies 27. States have an obligation under Articles 2(3) and 7 of the ICCPR to provide an effective remedy to those who have been tortured or subject to ill treatment. 323 28. This includes the ability to lodge a complaint, through a procedure which is ‘effective and reliable’,324 and which must be protected in domestic law.325 C. Safeguards for those deprived of their liberty Conditions of detention 29. Although also directly relevant to the right to liberty, detention conditions can amount to inhuman and degrading treatment and punishment, and even 318 Ibid. Ibid; and General Comment No.31, CCPR/C/21/Rev.1/Add/13 (2004), para 8. However, UNCAT is less specific on this point. 320 CAT, Communication 83/1997, GRB v Sweden, 15 May 1998, para 6.5. 321 CAT, Dzemajil and others v Yugoslavia, 21 November 2002. 322 CAT General Comment No.2, CAT/C/GC/2/CRP.1/Rev.4 (2007), para 18. 323 Human Rights Committee, General Comment No.20, 44th Session (1992), para 14. 324 CAT, UN doc. A/55/44, p. 22, para. 94 325 Ibid. 319 69