(1) In this section "derogation matter" means-
(a) a derogation by the United Kingdom from Article 5(1) of the Convention on Human Rights which relates to the detention of a person where there is an intention to remove or deport him from the United Kingdom, or
(b) the designation under section 14(1) of the Human Rights Act 1998 (c. 42) of a derogation within paragraph (a) above.
(2) A derogation matter may be questioned in legal proceedings only before the Special Immigration Appeals Commission; and the Commission-
(a) is the appropriate tribunal for the purpose of section 7 of the Human Rights Act 1998 in relation to proceedings all or part of which call a derogation matter into question; and
(b) may hear proceedings which could, but for this subsection, be brought in the High Court or the Court of Session.
(3) In relation to proceedings brought by virtue of subsection (2) -
(a) section 6 of the Special Immigration Appeals Commission Act 1997 (c. 68) (person to represent appellan