The legality of every internment during the Troubles will have to be scrutinised, the former Sinn Féin leader Gerry Adams has urged, after his convictions for escaping from the Maze prison were quashed by the supreme court. The unanimous decision of the UK’s highest court is likely to affect scores of claims from republicans and loyalists who are challenging their detention without trial during the 1970s. Five justices ruled that because the then secretary of state for Northern Ireland, Willie Whitelaw, had not personally considered whether to intern Adams, the requirements of the Detention of Terrorists (Northern Ireland) Order 1972 were not satisfied. Delivering judgment, Lord Kerr said: “It was clearly intended that the making of an [interim custody order] ICO, as opposed to the signing of the order, had to be the outcome of personal consideration by the secretary of state. In this case, a minister in the Northern Ireland Office had made the ICO. That minister could have signed the order, but he could not validly make it. “As a result, Mr Adams’ detention had not been lawfully authorised. His detention was therefore invalid, and it followed that he should not have been convicted of attempting to escape from lawful custody for the elementary but inevitable reason that the custody in which he had been detained was, in fact, not lawful. His appeal is therefore allowed, and his convictions are quashed.” Adams, 71, who has always denied being a member of the IRA, called on the government to identify and inform others whose internment may also have been unlawful. Between 1971 and 1975 almost 2,000 people were detained without trial. Documents released to the public records office under the 30-year rule revealed that the British prime minister at the time, Harold Wilson, knew there had been procedural irregularities in the detention of Adams and other republicans who tried to escape from the heavily guarded camp. “So the knowledge of my unlawful detention was known by the most senior level of the British system,” Adams said after the judgment. “Of course internment … was never lawful. In fact it set aside the normal principles of law and was based on a blunt and brutal piece of coercive legislation. I have no regrets about my imprisonment, except for the time I was separated from my family. “There is an onus on the British government to identify and inform other internees whose internment may also have been unlawful.” KRW Law, the Belfast solicitors acting on behalf of 15 former republican and 19 former loyalist internees, said their orders will have to be checked to see whether there had been “proper authorisation by the relevant secretary of state at the time of detention”. Those held were overwhelmingly nationalists or republicans; not all were members of paramilitary organisations. Adams was first interned in March 1972 and was released in June that year to take part in secret talks with the Conservative government in London. He was rearrested in July 1973 in Belfast and taken to the Maze, also known as Long Kesh detention centre. On Christmas Eve 1973 he was one of four detainees caught attempting to break out. A hole had been cut in a perimeter fence and all four men were already out of the prison. His second attempt, in July 1974involved kidnapping a man who had a striking resemblance to him from a bus stop in west Belfast. The man was taken to a house where his hair was dyed and he was given a false beard. His double was driven to the Maze where the plan was that he would be swapped for Adams in a visiting hut. Prison staff had been alerted, however, and Adams was arrested. The leader of the Ulster Unionist party, Steve Aiken, said IRA victims would be “left dismayed and angry” by the judicial decision.