admissible and judges and prosecutors fail to promptly and impartially investigate allegations of torture or other ill-treatment across the region.79 34. There are numerous reasons courts fail to implement the exclusionary rule. Laws that prohibit all forms of evidence obtained by torture, alone, might not be sufficient where there are no fair and effective procedures for challenging and establishing whether evidence has been obtained by torture, and for excluding such evidence. Suspects, accused persons and defendants should be able to initiate these procedures without any obstacles. For instance, the UN Special Rapporteur on Torture has noted that, in jurisdictions where independent medical examinations must be authorized by investigators, prosecutors or penitentiary authorities, those authorities might delay authorization so that any injuries deriving from torture have healed by the time an examination is conducted.80 The Rapporteur also found that these medical and forensic reports are often of such poor quality that they provide little assistance to judges or prosecutors when deciding whether to exclude statements.81 35. Decisions by regional courts and treaty monitoring bodies identify two distinct stages of procedures for challenging such evidence: (a) the initial stage of triggering the procedure to exclude evidence; and (b) the stage of establishing whether the evidence was obtained by torture. In order to trigger the procedure (stage a), defendants must bring a “prima facie” or “well founded” claim that torture has occurred.82 Once the initial prima facie test is satisfied (stage a), the burden of proof should then shift to the state to prove that the evidence was not obtained by torture if it is to be admitted (stage b).83 36. International human rights law leaves the specific nature of procedures to exclude torture evidence to the discretion of states. In many countries, the procedure takes the form of an investigation or a hearing within the trial to establish whether evidence was obtained by torture. In practice, the procedure to exclude torture evidence can present insurmountable challenges to suspects, accused persons or defendants. In particular, this can be the case where the state does not bear 79 80 81 82 83 See e.g. “Outcome report, Seventh Expert Forum on Criminal Justice for Central Asia (2018)”, organized by ODIHR, OHCHR, UNODC and OSCE field operations. Report of the Special Rapporteur on torture and other cruel, inhuman or degrading treatment or punishment, op. cit., note 73, para. 25. Ibid. Deolall v Guyana, CCPR/C/82/D/912/2000, 5 November 2004; Singarasa v Sri Lanka, CCPR/ C/81/D/1033/2001, 23 August 2004; GK v Switzerland, 12 May 2003, Communication No 219/2002, para 6.10. Ibid. See also report of the UN Special Rapporteur on torture and other cruel inhuman or degrading treatment or punishment, op. cit., note 73, para 17. 29