E/CN.4/2006/7/Add.2 page 20 and British Columbia, however, immigration detainees are automatically and invariably assigned to maximum security, on the ground that they are not expected to remain long enough in the “system” for an assessment to be viable. The holding of immigration detainees, who often have no criminal record, among the criminal population affects them adversely in various ways, impairing their ability to effectively challenge detention. As statistics show, longer periods of detention are associated with non-immigration facilities.4 81. The Working Group is particularly concerned by credible allegations that immigration detainees have been transferred from immigration holding centres to provincial criminal facilities as a reprisal for conduct such as claiming better treatment or conditions of detention. The Working Group was also told (both by civil society representatives and officials of the corrections system) that there is very poor communication between federal and provincial authorities with regard to the background, detention history and needs of immigration detainees. In the light of all this, the ongoing negotiation of a Memorandum of Understanding between the federal Government and the provinces regarding the matter gains particular importance. 82. These circumstances of immigration detention place a special burden on vulnerable persons, such as victims of trafficking. As the primary means to obtain release from immigration detention is the posting of a cash bond, persons who lack financial resources or have no connections in the country (often migrants smuggled into Canada without any belongings) face great difficulties obtaining release. 83. As with many of its other areas of concern, the Working Group observed commendable counter-measures also in this respect. Numerous, very active NGOs assist immigration detainees in their efforts to obtain release. With funding provided by government, the Toronto Bail Programme assists immigration detainees who otherwise would be denied release. 3. Detention under security certificates 84. Finally, regarding detention under the security certificate process, the Working Group wishes to stress that it is fully aware of the duty of the Canadian Government to protect its citizens from terrorist acts and to comply with its international obligations with regard to combating terrorism. It is also aware of the fact that there are only four men currently detained under this procedure. Nonetheless, the Working Group is gravely concerned about the following elements, which undermine the security certificate detainees’ rights to a fair hearing, to challenge the evidence used against them, not to incriminate themselves, and to judicial review of detention: − The security certificate procedure applies only to suspects who are not Canadian citizens; in fact, all four men currently detained under security certificates are Arab Muslims; − If the person certified is not a permanent resident, detention is mandatory; − The length of this detention without charges is indeterminate; the duration of the detention of the four persons currently detained under a security certificate ranges from four to six years;