The principles of observation and cooperation are disproportionately weighted in favour of the former, enabling the prison services to have an overall view of the development of the persons for which they are responsible, but not enabling prisoners to be really involved in their sentence execution programs. The latter are implemented in a fragmentary manner and experienced by the professionals, “as an element added to the constraints”. In the same manner, certain prisoners perceive the PEP to be an additional instrument of control and not a support tool. The Contrôleur Général recommends that precise, enforceable rules be instituted for the elaboration of PEPs and for following them up over time, including in case of transfer between institutions. He also recommends that the human resources essential to the success of this kind of follow-up tool should be put in place within institutions. 8.2 Differentiated Regimes: implementation vague criteria and widely differing In the 1980s, in order to offset the increase in the length of sentences by greater autonomy in prison, the opening of cell doors was instituted within penal institutions for convicted prisoners (long-term detention centres and long-stay prisons). In 2002, some of these institutions trialled the putting in place of a “closed doors” regime, which was extended to several other sites, until the distribution of a note from the prisons administration on 20th of July 2009 endorsing existing practices and planning to provide them with a better framework “in such a manner that they shall be a practical illustration of what the law will provide”. Shortly before this, following his visit to France between 21st and 23rd of May 2008, the Commissioner for Human Rights of the Council of Europe recommended that, within the framework of the reform of the Prisons Act in course, “the differentiated regimes should not be legalised.” However, the second paragraph of article 89 of the Prisons Act legalises the practice of applying different prison regimes to prisoners “taking their personality, health, dangerousness and efforts with regard to social rehabilitation into account”. The lack of precision of these criteria has been emphasised by the Contrôleur Général on numerous occasions. Thus, from his first public recommendations, concerning the inspection of the remand prison of Villefranche-sur-Saône180, the Contrôleur Général noted the risk of “pure and simple segregation between the various different buildings and stages of the institution, between prisoners likely to change in the course of their imprisonment and those marginalised, often in an irreversible manner, throughout the time of their imprisonment, in a passageway considered difficult both for them and for prison staff.” In the first place, it needs to be emphasised that these criteria in no way result from those prevailing in the establishment of different regimes as recommended by the Council of Europe through the European Prison Rules. Indeed, rule 51.4 provides that “each prisoner is […] subject to a security regime corresponding to the identified level of risk”. It is a question of assessing, on the one hand, the risk that the person presents to the community in case of escape and, on the other hand, the probability of their attempting to escape alone or with the help of outside accomplices. Thus defined, these criteria appear easily identifiable as compared to the aforementioned criteria established by the Prisons Act. The absence of details and definitions of notions such as personality and dangerousness leaves room for subjectivity and the risk of arbitrary measures, 180 Recommendation of 24th December 2008 concerning the aforementioned remand prison of Villefranche-sur-Saône. 117