16 49. The CPT has also expressed misgivings as regards the practice observed in certain countries of each operational department (narcotics, organised crime, anti-terrorism) in a police establishment having its own detention facility staffed by officers from that department. The Committee considers that such an approach should be discarded in favour of a central detention facility, staffed by a distinct corps of officers specifically trained for such a custodial function. This would almost certainly prove beneficial from the standpoint of the prevention of ill-treatment. Further, relieving individual operational departments of custodial duties might well prove advantageous from the management and logistical perspectives. 50. Finally, the inspection of police establishments by an independent authority can make an important contribution towards the prevention of ill-treatment of persons held by the police and, more generally, help to ensure satisfactory conditions of detention. To be fully effective, visits by such an authority should be both regular and unannounced, and the authority concerned should be empowered to interview detained persons in private. Further, it should examine all issues related to the treatment of persons in custody: the recording of detention; information provided to detained persons on their rights and the actual exercise of those rights (in particular the three rights referred to in paragraphs 40 to 43); compliance with rules governing the questioning of criminal suspects; and material conditions of detention. The findings of the above-mentioned authority should be forwarded not only to the police but also to another authority which is independent of the police.