ATCSA 2001:

PART 4
IMMIGRATION AND ASYLUM

S.21 Suspected international terrorists

Suspected international terrorist: certification

(1) The Secretary of State may issue a certificate under this section in respect of a person if the Secretary of State reasonably -

(a) believes that the person's presence in the United Kingdom is a risk to national security, and
(b) suspects that the person is a terrorist.

(2) In subsection (1)(b) "terrorist" means a person who-

(a) is or has been concerned in the commission, preparation or instigation of acts of international terrorism,
(b) is a member of or belongs to an international terrorist group, or
(c) has links with an international terrorist group.

(3) A group is an international terrorist group for the purposes of subsection (2)(b) and (c) if-

(a) it is subject to the control or influence of persons outside the United Kingdom, and
(b) the Secretary of State suspects that it is concerned in the commission, preparation or instigation of acts of international terrorism.

(4) For the purposes of subsection (2)(c) a person has links with an international terrorist group only if he supports or assists it.

Thus under Part IV of the Anti-Terrorism, Crime and Security Act 2001 the Home Secretary could, by executive action, certify that a "foreigner" be arrested and held indefinitely in detention. The UK had to derogate from Article 5 (the right to liberty) of the European Convention of Human Rights (ECHR) - the only EU state do so or to introduce such draconian powers. Such a derogation is only allowed where there is a "public emergency threatening the life of the nation".

Seventeen men, all Muslims, were detained having been certified as a "suspected international terrorist".

Part IV of the ATCSA 2001 has now lapsed as it was not renewed and its place taken by the Prevention of Terrorism Act 2005.