Birmingham pub bombings
The Birmingham pub bombings took place on 21 November 1974 and were attributed to the Provisional IRA. Explosive devices were placed in two central Birmingham pubs: the Mulberry Bush at the foot of the Rotunda, and the Tavern in the Town – a basement pub in New Street. The resulting explosions, at 20:25 and 20:27, collectively were the most injurious attacks in Great Britain since World War II (until surpassed by the 7 July 2005 London bombings); 21 people were killed (ten at the Mulberry Bush and eleven at the Tavern in the Town) and 182 people were injured. A third device, outside a bank in Hagley Road, failed to detonate.
Arrests and questioning
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. (March 2018)
Six men were arrested, of whom five were Belfast-born Roman Catholics, while John Walker was a Roman Catholic born in Derry. All six had lived in Birmingham since the 1960s. All the men except for Callaghan had left the city early on the evening of 21 November from New Street Station, shortly before the explosions. They were travelling to Belfast to attend the funeral of a Provisional Irish Republican Army member who had accidentally killed himself while planting a bomb in Coventry.
When they reached Heysham they and others were subject to a Special Branch stop and search. The men did not tell the police of the true purpose of their visit to Belfast, a fact that was later held against them. While the search was in progress the police were informed of the Birmingham bombings. The men agreed to be taken to Morecambe police station for forensic tests.
On the morning of 22 November, after the forensic tests and questioning at the hands of the Morecambe police, the men were transferred to the custody of West Midlands Serious Crime Squad police unit. William Power alleged that he was assaulted by members of Birmingham Criminal Investigation Department. Callaghan was taken into custody on the evening of 22 November.
While the men were in the custody of the West Midlands Police they were deprived of food and sleep, they were interrogated sometimes for up to 12 hours without a break; threats were made against them and the beatings started: ranging from punches, letting dogs within a foot of them and being the subjects of a mock execution. Power confessed while in Morecambe while Callaghan, Walker and McIlkenny confessed at Queens Road in Aston; Hill and Hunter did not sign any documents.
On 12 May 1975 the six men were charged with murder and conspiracy to cause explosions. Three other men, James Kelly, Michael Murray and Michael Sheehan, were charged with conspiracy and Kelly and Sheehan also faced charges of unlawful possession of explosives.
The trial began on 9 June 1975 at the Crown Court sitting at Lancaster Castle, before Mr Justice Bridge and a jury. After legal arguments the statements made in November were deemed admissible as evidence. The unreliability of these statements was later established. Thomas Watt provided circumstantial evidence about John Walker's association with Provisional IRA members.
Forensic scientist Dr Frank Skuse used positive Griess test results to claim that Hill and Power had handled explosives. Callaghan, Hunter, McIlkenny and Walker all had tested negative. GCMS tests at a later date were negative for Power and contradicted the initial results for Hill. Skuse's claim that he was 99% certain that Power and Hill had explosives traces on their hands was opposed by defence expert Dr Hugh Kenneth Black of the Royal Institute of Chemistry, the former HM Chief Inspector of Explosives, Home Office. Skuse's evidence was clearly preferred by Bridge. The jury found the six men guilty of murder. On 15 August 1975, they were each sentenced to 21 life sentences.
Criminal charges against prison officers and civil actions against police
On 28 November 1974, the men appeared in court for the second time after they had been remanded into custody at HM Prison Winson Green. All showed bruising and other signs of ill-treatment. Fourteen prison officers were charged with assault in June 1975, but were all acquitted at a trial presided over by Mr. Justice Swanwick. The Six brought a civil claim for damages against the West Midlands Police in 1977, which was struck out on 17 January 1980 by the Court of Appeal (Civil Division), constituted by the Master of the Rolls, Lord Denning, Goff LJ and Sir George Baker, under the principle of estoppel.
During proceedings, prison officers and police were blamed for the beatings.
In March 1976 their first application for leave to appeal was dismissed by the Court of Appeal, presided over by Lord Widgery CJ. Journalist Chris Mullin investigated the case for Granada TV's World in Action series. In 1985, the first of several World in Action programmes casting doubt on the men's convictions was broadcast. In 1986, Mullin's book, Error of Judgment: The Truth About the Birmingham Pub Bombings, set out a detailed case supporting the men's claims that they were innocent. It included his claim to have met some of those who were actually responsible for the bombings.
The Home Secretary, Douglas Hurd, referred the case back to the Court of Appeal. In January 1988, after a six-week hearing (at that time the longest criminal appeal hearing ever held), the convictions were ruled to be safe and satisfactory. The Court of Appeal, presided over by the Lord Chief Justice Lord Lane, dismissed the appeals. Over the next three years, newspaper articles, television documentaries and books brought forward new evidence to question the safety of the convictions, while campaign groups calling for the men's release were formed in Britain, Ireland, Europe and the US.
Their second full appeal, in 1991, was allowed. Hunter was represented by Lord Gifford QC, the others by Michael Mansfield QC. New evidence of police fabrication and suppression of evidence, the successful attacks on both the confessions and the 1975 forensic evidence caused the Crown to decide not to resist the appeals. The Court of Appeal, constituted by Lord Justices Lloyd, Mustill and Farquharson, stated that "in the light of the fresh scientific evidence, which at least throws grave doubt on Dr. Skuse's evidence, if it does not destroy it altogether, these convictions are both unsafe and unsatisfactory."  On 14 March 1991 the six walked free.
In 2001, a decade after their release, the six men were awarded compensation ranging from £840,000 to £1.2 million.
The success of the appeals and other miscarriages of justice caused the Home Secretary to set up a Royal Commission on Criminal Justice in 1991. The commission reported in 1993 and led to the Criminal Appeal Act 1995 which established the Criminal Cases Review Commission in 1997. Superintendent George Reade and two other police officers were charged with perjury and conspiracy to pervert the course of justice but were never prosecuted. During the inquest into the bombings in 2016, Hill stated that he knew the identities of three of the bombers who were still "free men" in Ireland.