The Prevention of Terrorism Acts were a series of Acts of the Parliament of the United Kingdom from 1974 to 1989 that conferred emergency powers upon police forces where they suspected terrorism. The direct ancestor of the bill was the Prevention of Violence Act 1939 (Temporary Provisions) which was brought into law in response to an Irish Republican Army (IRA) campaign of violence under the S-Plan. The Prevention of Violence Act was allowed to expire in 1953 and was repealed in 1973 to be reintroduced under the Prevention of Terrorism (Temporary Provisions) Act. In 2000, the Acts were replaced with the more permanent Terrorism Act 2000, which contained many of their powers, and then the Prevention of Terrorism Act 2005, 2006 and 2008 Acts followed.

The first Act was enacted in 1974 following the IRA bombing campaigns of the early 1970s. The Act was introduced by Roy Jenkins, then Home Secretary, as a severe and emergency reaction to the Birmingham pub bombs. The apparent chronology was that there were pub bombings by the IRA in Birmingham on 21 November 1974. 21 people died and 184 were injured. There was a strong desire to respond to what was perceived as "the greatest threat [to the country] since the end of the Second World War." (H.C. Debs. Vol. 882 col. 743 28 November 1974, Mr. Lyons.) The conception of the Bill was announced on 25 November, when the Home Secretary warned that: "The powers... are Draconian. In combination they are unprecedented in peacetime.' (Ibid. col. 35 25 November 1974, Mr. Jenkins). Parliament was supportive and had passed the Bill by the 29th November, virtually without amendment or dissent. The Bill passed through the Commons on 28 and 29 November and passed through Lords on 29 November. In fact, much of the Bill had been drafted in secrecy during the previous year, as shown in the only full length commentary on the legislation by Clive Walker (See: The Prevention of Terrorism in British Law (2nd ed., Manchester University Press, 1992).

It was rewritten in 1976, 1984 and again in 1989, but continued to stay as emergency 'temporary' powers, that had to be renewed each year. The first three Acts all contained final date clauses beyond the annual renewal, this provision was not included in the 1989 Act.

From 2000 to the present, the British Parliament passed a series of Terrorism Acts that were aimed at terrorism in general, rather than specifically focussed on terrorism related to Northern Ireland. The timings were influenced by the September 11, 2001 attacks and 7 July London bombings, as well as the politics of the Global War on Terrorism, according to the politicians who announce them as their response to a terrorism act. Between them, they provided a definition of terrorism that made it possible to establish a new and distinct set of police powers and procedures, beyond those related to ordinary crime, which could be applied in terrorist cases.

The Terrorism Act 2000

 

• gave a broad definition of terrorism for the first time
• provided for an extended list of proscribed terrorist organizations beyond those associated with Northern Ireland.
• allowed police to detain terrorist suspects for questioning for up to 7 days.

The Anti-terrorism, Crime and Security Act 2001

 

• passed in the aftermath of the September 11, 2001 attacks
• contained measures that had been rejected from the 2000 Act.
• allowed Ministry of Defence Police to operate outside of military bases even for non-terrorist cases.
• Part 4 enabled foreigners to be detained as terrorist suspects indefinitely.
• required annual renewal of some provisions in recognition of the political climate

The Criminal Justice Act 2003

 

• doubled the period of detention of a terrorist suspect for questioning to 14 days.
• justified by the claim that forensic analysis of chemical weapons materials might not be complete in 7 days.

The Anti-terrorism, Crime and Security Act 2001 (Continuance in force of sections 21 to 23) Order 2003

 

• renewed Part 4 of the 2001 Act.
• voted on specifically by Parliament due to its controversial nature.

Judgement by the Law Lords on Part 4 of the 2001 Act (2004)

 

• found in favour of a terrorist suspect who had been detained without charge for over two years
• set a time limit for their release

The Prevention of Terrorism Act 2005

 

• established the "control order" which is a form of house arrest
• was subject to extended Parliamentary dispute which lasted for over 50 hours
• passed just in time to be applied to the Part 4 terrorist suspects

The Terrorism Act 2006

 

• drafted in the aftermath of the 7 July 2005 London bombings
• defines the offence of "glorifying" terrorism
• revises the period of detention of terrorist suspect without charge up to 28 days
  • the government had asked for this to be 90 days, but was defeated in a vote
• justified by the claim that necessary evidence to decide charges might be encrypted on one of thousands of hard disks, and it could take this long to search them.^[9]

The Counter-Terrorism Act 2008

 

• allows police questioning of suspects after they have been charged
• requires convicted terrorist to notify the police of their whereabouts (similar to existing requirements for sex offenders)
• government defeat of extending period of detention without charge to 42 days.
• interpreted as banning all photographs of the police in public places.