Amal Clooney is set to travel to Belfast next month to meet nine claimants who want the European Court of Human Rights (ECHR) to rule that Edward Heath’s government was complicit in the torture of Irish nationalists.

Fourteen detainees were subjected to ‘deep interrogation techniques’ after the arrest of hundreds of suspected IRA members in 1971.

A previous ECHR appeal ruling in 1978 stated that the techniques “amounted to a practice of inhuman and degrading treatment”, but did not match “the particular intensity and cruelty implied by the word torture”.

Last year, the government of Ireland asked the ECHR to revise its judgement.

Its renewed interest in the case was sparked when an RTÉ documentary uncovered a memo sent by contemporary home secretary Merlyn Rees to prime minister James Callaghan in 1977, referring to “a political decision” being made to authorise “methods of torture” in 1971/72.

The memo is being cited as evidence that the alleged torture of detainees was well known and recognised at the highest tiers of government during The Troubles.

The nine claimants who will be meeting with Clooney, a respected human rights lawyer who has represented WikiLeaks founder Julian Assange, to discuss their experience of being hooded and denied food and water, as well as being subjected to stress positions, extended periods of loud noise, and sleep deprivation.

They are among only fourteen Irish republican suspects who were subjected to all of the ‘five techniques’, which were eventually banned in the UK.

They also claim to have once been hooded and thrown from a helicopter, believing that they would fall to their death - though the helicopter was hovering only a few metres from the ground.

Jim McIlmurray, a historian helping to co-ordinate the legal action, told The Sunday Times that Amal Clooney was a welcome addition to the team, but hoped that her participation would not turn the case into a media circus.

Her husband, actor George Clooney, is expected to join her on the trip to Belfast.