indicators in the classification of radicalization, and that prisoners could not challenge 206 their classifications. Lack of transparency and application of indicators without sufficient procedural safeguards Practice example 3: In one country, those believed to have been radicalized to terrorism or violence (and, therefore, presumed security threats) are registered on a specific list and subject to various measures, from keeping a diary of their observed activities to contact limitation, solitary confinement and, sometimes, placement in so-called “D-Rad:Ex wings” (special units in prisons for detainees considered to present the greatest risk of violent radicalization). The UN Special Rapporteur on Counter-Terrorism expressed concern that the procedure for placing an individual in one of these wings was opaque and there 207 was no review process. Prison staff did continually assess “signs of radicalization” and 208 categorize the prisoners accordingly. The prisoners, however, were not informed of these assessments or their implications, nor was there a process for them to challenge the assessment. The Special Rapporteur emphasized the complexity of identifying radicalization to violence or terrorism, the need for specialized trained professionals, transparency and consistency, and the risks of associating genuine religious practice 209 with radicalization. Practice example 4: In another country, the UN Special Rapporteur on Counter-Terrorism has noted that in the so-called “radicalization evaluation units”, where prisoners convicted of terrorist acts spend four months and where, through multi-disciplinary approaches, 210 their level of radicalization to violence or terrorism and risk potential is assessed, prison staff seemed knowledgeable and aware of the challenges of risk and needs assessment practices. However, at the same time, the Rapporteur’s report raised concerns about the transparency and consistency of the risk assessment procedure involving different professionals, as well as about the lack of the possibility to appeal placement decisions and the way in which the four-month assessment period in the unit was used as a 211 justification for the low level of activities available for detainees. 206 Report of the UN Special Rapporteur on Counter-Terrorism, Visit to Kazakhstan, op. cit., note 108, para. 35. 207 Report of the UN Special Rapporteur on Counter-Terrorism, Visit to Belgium, A/HRC/40/52/Add.5, 8 May 2019, para. 38. See also: Comité T, “Assessment of Measures to Combat Terrorism in the Light of Human Rights,” 2020. 208 Ibid., para. 39: Prison authorities continually assess signs of radicalization exhibited by inmates. Those considered radicalized or at risk of radicalization (so-called “CelEx” detainees) will fall into one of the following categories: category A (convicted of or charged with terrorism); category B (so-called “assimilated persons” whose files indicate a connection with terrorism); category C (foreign terrorist fighters); and category D (detainees who evidence signs of radicalization). Three further categories are to be added to this classification system, including “home-grown terrorists” and “hate preachers”. 209 Ibid., para. 40. 210 Report of the UN Special Rapporteur on Counter-Terrorism, Visit to France, A/HRC/40/52/Add.4, 8 May 2019, para. 43 on the radicalization evaluation units (“Quartier d’évaluation de la radicalization” or QER). 211 CGLPL , «Prise en charge pénitentiaire des personnes ‘radicalisées’ et respect des droits fondamentaux”, January 2020, p. 32; Report of the UN Special Rapporteur on Counter-Terrorism, Visit to France, ibid., para. 42. 47