Places visited by the National Preventive Mechanism in 2011 2.1. Prisons and pre-trial detention centres In 2011, the representatives of the Human Rights Defender, acting as the National Preventive Mechanism28, carried out visits to 12 prisons29, including one revisit30, and to 4 pre-trial detention centres31. Figure 2. The number of visits under the National Preventive Mechanism to pre-trial detention centres and prisons between 2008 and 2011. 50 45 40 35 30 25 20 12 5 16 4 10 10 15 10 5 0 2011 2010 2009 2008 13 Prisons 16 Pre-trial detention centres a) Overcrowding The visiting teams checked on each occasion whether the rooms for prisoners were not overcrowded. According to the heads of visited establishments, the problem of overcrowding did not exist in their facilities. However, the findings made during the visits by the NPM employees often revealed that overcrowding was eliminated only in statistical terms. This effect has been achieved by applying improper practices. For example, recreation rooms were adapted to accommodate persons under temporary arrest (Prison in Kluczbork), patient rooms were included among the ordinary prison cells (Pre-Trial Detention Centre in Grójec, Prison in Płock, Prison in Nowy Wiśnicz) or some persons were kept in transition cells for excessively long periods (Prison in Płock). Therefore, on 8 June 2011 the Human Rights Defender requested32 the Director General of the Prison Service to address the fact that the heads of some penitentiary establishments fail to report the actual overcrowding in their establishments. In reply, the Director  Hereinafter referred to as “NPM” or “Mechanism.”  Prisons in Kluczbork, Tarnów–Mościce, Płock, Koronowo, Nowy Wiśnicz, Nowogard, Łupków, Jasło, Wadowice, Trzebinia, Uherce Mineralne, Sieradz. 30  Prison in Płock. 31  Pre‑trial detention centres in Grójec, Mysłowice, Giżycko, Olsztyn. 32  RPO-665674-VII/11. 28 29 29