Immigration Appeals Commission, or SIAC in short, is required to review every certificate, by way of appeal or otherwise, and form its own view on whether reasonable grounds currently exist for believing a person’s presence is a risk to national security and for suspecting he is a terrorist: sections 25 and 26. If SIAC considers these grounds do not exist the certificate must be cancelled. Thus the certificate issued by the Secretary of State will lead nowhere if SIAC considers reasonable grounds do not exist. The certificate, although a prerequisite to exercise of the Secretary of State’s powers under the Act, will be comparatively short-lived in its effect if SIAC considers the necessary reasonable grounds do not exist. In other words, the certificate is in the nature of an essential preliminary step. 76. For its part, in forming its own view on whether reasonable grounds exist SIAC is discharging a judicial function which calls for proof of facts by evi dence. The ethical ground on which information obtained by torture is not admissible in court proceedings as proof of facts is applicable in these cases as much as in other judicial proceedings. That is the present case. 77. Similar problems are bound to arise with other counter-terrorism legislation. One instance concerns decisions by the Secretary of State to deport on the ground that deportation is conducive to the public good as being in the interests of national security. An appeal lies to SIAC, which must allow an appeal if the decision involved the exercise of discretion by the minister and SIAC considers the discretion should have been exercised differently: section 2 of the Special Immigration Appeals Commission Act 1997, as substituted by the Nationality, Immigration and Asylum Act 2002. Another instance concerns non-derogating control orders made by the Secretary of State under section 2 of the Prevention of Terrorism Act 2005. Here the role of the court is expressed to be of a different and more limited character than under the 2001 Act. Under the 2005 Act the supervisory role of the court regarding non-derogating control orders is essentially limited to considering whether the relevant decision of the Secretary of State is ‘flawed’. In deciding this issue the court must apply the ‘principles applicable on an application for judicial review’: section 3(11). 78. Whether the Secretary of State may take tainted information into account when making decisions under statutory provisions such as these, and whether SIAC’s function requires or permits evidence to be given of all the matters taken into account by the Secretary of State, are questions for another day. They do not call for decision on these appeals, and they -51-