The Birmingham Six – Paddy Joe Hill, Hugh Callaghan, Richard McIlkenny, Gerry Hunter, Billy Power and Johnny Walker – are released from jail on March 14, 1991 after their convictions for the murder of 21 people in two pubs are quashed by the Court of Appeal.

The Birmingham pub bombings take place on November 21, 1974 and are attributed to the Provisional Irish Republican Army. Explosive devices are 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. Up until this point, the resulting explosions collectively are the most injurious attacks in Great Britain since World War II. Ten people at the Mulberry Bush and eleven at the Tavern in the Town are killed and 182 people are injured. A third device, outside a bank in Hagley Road, fails to detonate.

Five of the six are taken into custody on the evening of November 21. The men agree to be taken to Morecambe police station for forensic tests.The following morning, after the forensic tests and questioning at the hands of the Morecambe police, the men are transferred to the custody of West Midlands Serious Crime Squad police unit. Hugh Callaghan is taken into custody on the evening of November 22.

On May 12, 1975 the six men are charged with murder and conspiracy to cause explosions. The trial begins on June 9, 1975 at the Crown Court sitting at Lancaster Castle. After legal arguments the statements made in November are deemed admissible as evidence. The unreliability of these statements is later established. Forensic scientist Dr. Frank Skuse uses positive Griess test results to claim that Hill and Power had handled explosives. Callaghan, Hunter, McIlkenny and Walker all had tested negative. The jury finds the six men guilty of murder. On August 15, 1975, they are each sentenced to 21 life sentences.

In March 1976 their first application for leave to appeal is dismissed by the Court of Appeal. Their second full appeal, in 1991, is allowed. New evidence of police fabrication and suppression of evidence, the successful attacks on both the confessions and the 1975 forensic evidence causes the Crown to decide not to resist the appeals. The Court of Appeal states 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 March 14, 1991 the six walk free.

In 2001, a decade after their release, the six men are awarded compensation ranging from £840,000 to £1.2 million.

The success of the appeals and other miscarriages of justice cause the Home Secretary to set up a Royal Commission on Criminal Justice in 1991. The commission reports in 1993 and leads to the Criminal Appeal Act 1995 which establishes the Criminal Cases Review Commission in 1997. Superintendent George Reade and two other police officers are charged with perjury and conspiracy to pervert the course of justice but are never prosecuted. During the inquest into the bombings in 2016, Hill states that he knows the identities of three of the bombers who are still “free men” in Ireland.