A/HRC/10/21 page 26 shortest period of time. Alternatives to detention must 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. 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. 83. Finally, the Working Group requests States and other stakeholders to provide the Group with information and share their experiences regarding the installation of video and/or audio (recording) equipment in rooms where interrogations related to criminal investigations are conducted. The Working Group has taken note of a seemingly recent tendency of international and regional human rights bodies recommending to States the implementation of such measures to prevent the extraction of confessions under torture or other forms of ill-treatment and their admission as evidence in criminal trials. It considers that the issue warrants further study. -----