Held, (1) article 1(3) of Council Framework Decision 2002/584/JHA, read in conjunction with article 4 of the Charter of Fundamental Rights of the European Union, meant that when the executing judicial authority had objective, reliable, specific and properly updated information showing there to be systemic or generalised deficiencies in the detention conditions in the prisons of the member state issuing a European arrest warrant, it had to take account of all the relevant physical aspects of those conditions in the prison in which it was actually intended that the requested person would be detained, such as the personal cell space available to each detainee, sanitary conditions and the extent of the detainee’s freedom of movement within the prison, in order to assess whether there were substantial grounds for believing that, following the surrender to the issuing member state, the requested person would run a real risk of being subjected to inhuman or degrading treatment within the meaning of article 4 of the Charter. That assessment was not limited to the review of obvious inadequacies. For the purposes of that assessment, the executing judicial authority had to request from the issuing judicial authority the information that it deemed necessary and had to rely on the assurances given by the issuing judicial authority, in the absence of any specific indications that the detention conditions infringed article 4 of the Charter. It was, therefore, only in exceptional circumstances, and on the basis of precise information, that the executing authority could find that there was a real risk of the person being subjected to inhuman or degrading treatment because of the detention conditions, notwithstanding any assurance given by the issuing authority (judgment, paras 61, 62, 64, 66, 67–69, 85, operative part).

(2) For the purposes of assessing whether there was a real risk of the person being subjected to inhuman or degrading treatment, it was necessary to take account of the criteria laid down by the European Court of Human Rights in the light of article 3 of the Convention for the Protection of Human Rights and Fundamental Freedoms in calculating the minimum space required by a detainee in a multi-occupancy cell. Although the calculation should not take account of the area occupied by sanitary ware, it should include space taken up by furniture. Detainees had, however, still had be able to move around normally within the cell (judgment, paras 77, 85, operative part).

(3) The executing judicial authority could not rule out the existence of a real risk of inhuman or degrading treatment merely because the requested person had, in the issuing member state, a legal remedy enabling him to challenge the conditions of his detention or because there were, in the issuing member state, legislative or structural measures that were intended to reinforce the monitoring of detention conditions (judgment, paras 82, 85, operative part).

(4) A finding by the executing judicial authority that there were substantial grounds for believing that, following the surrender of the requested person to the issuing member state, that person would run a risk of being subjected to any inhuman or degrading treatment within the meaning of article 4 of the Charter, because of the detention conditions prevailing in the prison in which it was actually intended that he would be detained, could not be weighed against considerations relating to the efficacy of judicial co-operation in criminal matters and to the principles of mutual trust and recognition, for the purposes of deciding on that surrender (judgment, paras 83, 84, 85, operative part).