The Act allowed the Home Secretary to impose "control orders" on people who were suspected of involvement in terrorism, which in some cases may have derogated (opted out) from human rights laws.

The Bill was exchanged between the two chambers several more times that parliamentary day, which extended well into 11 March and led to the longest sitting of the House of Lords in its history, of over 30 hours.

That the Bill was "ping-ponged" between both houses was evidence of an unusual constitutional crisis,[dubious – discuss] notable because the urgency of the legislation – the previous powers to detain the individuals in HMP Belmarsh and elsewhere were due to expire on 14 March 2005 – meant that the Parliament Acts 1911 and 1949, the usual device to handle situations where the Commons and Lords cannot agree on a measure, could not be invoked in order to acquire Royal Assent without the consent of the upper house.

Eventually, a compromise was agreed, with both sides claiming victory: the opposition parties conceded all their amendments for the promise of a review of the legislation a year later.

The Bill received royal assent later that day, and the first control orders, to deal with the ten suspects previously interned in HMP Belmarsh, were issued by Charles Clarke, the Home Secretary, immediately.

Some critics were still unhappy with the compromise reached in the evening of 11 March, pointing out that an Act that removes the 790-year-old principle of habeas corpus, codified in Magna Carta, should not have been rushed through Parliament in the first place and that a review leaves it to the opposition to defeat the legislation, unlike a sunset clause, which would require the government to prove that these extraordinary powers were still a necessary and proportionate response to the threat of terrorism in the UK; comparisons were made with the detention provisions of South Africa's apartheid-era Terrorism Act No 83 of 1967.

[4] Mr Justice Sullivan held: To say that the Act does not give the respondent in this case, against whom a non-derogating control order has been made by the Secretary of State, a fair hearing in the determination of his rights under Article 6 of the Convention would be an understatement.

That controlees' rights under the Convention are being determined not by an independent court in compliance with Article 6.1, but by executive decision-making, untrammelled by any prospect of effective judicial supervision.

Following Secretary of State for the Home Department v JJ the House of Lords held that the restrictions imposed within the control would be open to challenge on the basis of incompatibility, with focus on Art.

Consequently, it was viewed as an anomaly for the Home Secretary to enforce harsher conditions on an individual who has not been convicted of any crime, in comparison with an open prisoner who enjoys freedom of association.