A/HRC/10/21 page 23 suitable and adequate for them, in order to eradicate corruption from its system of administration of justice. The Working Group calls on those States which have not yet become a party to this Convention to ratify, accept, approve or accede to it. D. Detention of immigrants in irregular situations 65. The Working Group has noted with concern, during the period reported upon, a development yet again towards tightening restrictions, including deprivation of liberty, applied to asylum-seekers, refugees and immigrants in an irregular situation even to the extent of making the irregular entry into a State a criminal offence or qualifying the irregular stay in the country as an aggravating circumstance for any criminal offence. 66. The Working Group has also publicly expressed, together with other mandate holders of special procedures, its concern regarding a law-making initiative of a regional organization comprising mainly receiving countries which would allow concerned States to detain immigrants who are in an irregular situation for a period of time of up to 18 months, pending removal. It would also be permitted to detain unaccompanied children, victims of human trafficking, and other vulnerable groups. 67. It was felt that States should be reminded that detention shall be the last resort and permissible only for the shortest period of time and that alternatives to detention should be sought whenever possible. Grounds for detention must be clearly and exhaustively defined and the legality of detention must be open for challenge before a court and regular review within fixed time limits. Established time limits for judicial review must even stand in “emergency situations” when an exceptionally large number of undocumented immigrants enter the territory of a State. Provisions should always be made to render detention unlawful if the obstacle for identifying immigrants in an irregular situation or carrying out removal from the territory does not lie within their sphere, for example, when the consular representation of the country of origin does not cooperate or legal considerations - such as the principle of non-refoulement barring removal if there is a risk of torture or arbitrary detention in the country of destination - or factual obstacles - such as the unavailability of means of transportation - render expulsion impossible. 68. In conclusion, the Working Group feels duty bound to reiterate that immigrants in irregular situations should not be qualified or treated as criminals and be viewed only from the perspective of national security. E. Video and audio recording of criminal interrogations 69. The Working Group is aware of a seemingly recent tendency of various international and regional human rights bodies recommending to Governments the installation of video and/or audio (recording) equipment in rooms where interrogations related to criminal investigations are undertaken. Such recommendations vary with respect to their scope. At times it is advised that such equipment be installed in police stations only. In other instances it is proposed to extend the measure to investigators’ or prosecutors’ offices, or all rooms where law enforcement authorities have relevant competencies. Such recommendations are made to Governments of States regarding which there are concerns about confessions obtained under torture or other forms of