Operation Demetrius

Operation Demetrius
Part of the Troubles and Operation Banner
The entrance to Compound 19, one of the sections of Long Kesh internment camp
Location	Northern Ireland
Objective	Arrest of suspected Irish republican militants
Date	9–10 August 1971 04:00 – ? (UTC+01:00)
Executed by	British Army Royal Ulster Constabulary
Outcome	1,981 people arrested and interned in total, firstly 342 7,000 civilians displaced
Casualties	(see below)

Operation Demetrius was a British Army operation in Northern Ireland on 9–10 August 1971, during the Troubles. It involved the mass arrest and internment (imprisonment without trial) of people suspected of being involved with the Irish Republican Army (IRA), which was waging an armed campaign for a united Ireland against the British state. It was proposed by the Unionist government of Northern Ireland and approved by the British Government. Armed soldiers launched dawn raids throughout Northern Ireland and arrested 342 in the initial sweep, sparking four days of violence in which 20 civilians, two IRA members and two British soldiers were killed. All of those arrested were Irish republicans and nationalists, the vast majority of them Catholics. Due to faulty and out-of-date intelligence, many were no longer involved in republican militancy or never had links with the IRA.^[1] Ulster loyalist paramilitaries were also carrying out acts of violence, which were mainly directed against Catholics and Irish nationalists, but no loyalists were included in the sweep.^[1]

The introduction of internment, the way the arrests were carried out, and the abuse of those arrested, led to mass protests and a sharp increase in violence. Amid the violence, about 7,000 people fled or were forced out of their homes.

The policy of internment lasted until December 1975 and during that time 1,981 people were interned;^[2] 1,874 were nationalist, while 107 were loyalist. The first loyalist internees were detained in February 1973.^[1]

The interrogation techniques used on some of the internees were described by the European Commission of Human Rights in 1976 as torture, but the superior court, the European Court of Human Rights (ECHR), ruled on appeal in 1978 that while the techniques were "inhuman and degrading", they did not constitute torture in this instance.^[3] It was later revealed that the British government had withheld information from the ECHR and that the policy had been authorized by British government ministers.^[4] In light of the new evidence, in 2014 the Irish government asked the ECHR to revise its judgement,^[5] but the ECHR eventually declined the request. In 2021, the Supreme Court of the United Kingdom found that the use of the five techniques amounts to torture.^[6]