E/CN.4/2006/7/Add.2 page 3 the immigration law governing the detention of asylum-seekers and migrants. The application of these provisions by immigration officials, as well as the limits the law places on judicial oversight over such application, give rise to instances in which aliens are unjustifiably detained and unable to effectively challenge detention. The Working Group also describes practical aspects of the detention of aliens under immigration law that result in considerable difficulties in challenging detention: cultural and language barriers, obstacles to the access to legal counsel and to assistance by NGOs, as well as the co-mingling with criminal detainees in high-security prisons. Finally, the Working Group expresses grave concerns at the security certificate process. This procedure allows the Government to detain aliens for years on the suspicion that they pose a security threat, without raising criminal charges. Judicial review of detention occurs at excessively long intervals and does not go to the merits of the need to maintain the individual in detention. The detainee’s ability to challenge detention is severely hampered by the fact that - in order to protect confidential information - he receives only a very superficial summary of the reasons for his detention. On the basis of its findings, the Working Group makes recommendations to the Government in the areas of the overrepresentation of Aboriginals in the prisons, the excessive use of pretrial detention with regard to accused belonging to vulnerable social groups, and unmet needs for legal aid. As far as detention under immigration law is concerned, the Working Group recommends some changes to law and/or policy. Finally, the Working Group recommends that terrorism suspects be detained in the criminal process, with the attached safeguards, and not under immigration laws.