-35 is deprived of liberty, any recourse to physical force which has not been made strictly necessary by his own conduct diminishes human dignity and is an infringement of Article 3 ECHR.52 As soon as force is used against a prisoner for one of the purposes indicated under Art 1 of the United Nations Convention against Torture (CAT), i.e. extracting a confession, intimidation, punishment and discrimination, any infliction of severe pain or suffering is to be qualified as torture, which means that it will be absolutely prohibited under any circumstances and no proportionality test will be allowed.53 3.2.2. Ensuring accountability and protecting victims of violence Establishing an effective complaint mechanism as well as investigating and prosecuting instances of violence are crucial steps to ensure accountability according to international standards and to foster a climate of trust in prison (see in this series the Handbook on Complaints).54 Equally important to this end are the establishment of appropriate procedures, such as the systematic recording and documentation of injuries, closed circuit television (CCTV) monitoring as well as guaranteeing victims’ rights and protection against reprisals. Medical personnel plays a central role in this regard. They can contribute to the prevention of violence against detained persons and more specifically of torture and ill-treatment, through the systematic recording and documentation of injuries.55 Access to medical examinations by a qualified health-care professional should be granted as soon as possible after a person is admitted to a place of detention or whenever they were involved in a violent incident.56 52. ECtHR, Tali v Estonia, No 66393/10, 13 February 2014, § 59; ECtHR, Artyomov v Russia, No 14146/02, 27 May 2010, § 145; ECtHR, Bouyid v Belgium, No 23380/09, 28 September 2015, § 101; see also ECtHR, Guide: Prisoners’ Rights. 53. Nowak/Birk/Monina 58ff. 54. Detailed guidance on the modalities of such investigations can be found in the following documents: Manual on the Effective Investigation and Documentation of Torture and Other Cruel, Inhuman or Degrading Treatment or Punishment: Istanbul Protocol (United Nations Publication 2004) HR/P/PT/8/Rev.1. See also the CoE, Effective Investigation of Ill-Treatment: Guidelines on European Standards (CoE 2014). 55. UNGA, ‘Body of Principles for the Protection of All Persons under Any Form of Detention or Imprisonment’, Res 43/173 of 9 December 1988 (Body of Principles) Principle 24; EPR Rules 16 and 42; and Mandela Rules, Rules 34 and 46. See also CoE, CM, ‘Recommendation No R(98) 7 of the committee of Ministers to Member States Concerning the Ethical and Organisational Aspects of Health Care in Prison’ (1998) R(98)7; and by the CPT standards regarding health care services in prisons, particularly CPT, ‘3rd General Report on the CPT’s Activities, 1 January-31 December 1992’ (1993) CPT/Inf (93) 12, 13ff. For more details see also Dignity 2020, and PRI and others, Guidance Document, 157ff. 56. See EPR Rule 42.3(c);Mandela Rules; CPT, ‘Developments Concerning CPT Standards in Respect Monitoring Prison Violence