Conservative threats to withdraw from European human rights legislation would create a fresh crisis in the already fragile Northern Ireland peace process, a civil liberties organisation has warned.

Abolishing human rights law in the UK would be incompatible with and undermine the 1998 Good Friday agreement which brought peace and stability to the former war torn region according to the committee on the administration of justice.

The CAJ, which has been highlighting state and security forces’ abuses both during and after the Troubles for decades, also said that if the Conservative party forced the UK out of Europe’s human rights regime it would shatter confidence within communities over politically sensitive policing reforms.

They pointed out on Friday that since the Patten reforms of policing all police officers in the region are obliged to abide by the European convention on human rights, which has force in UK law via the Human Rights Act 1998. The move was designed to enshrine confidence and build support within the nationalist community for the Police Service of Northern Ireland.

During the Troubles many nationalist and republicans regarded the RUC as a quasi-military force that committed a number of human rights abuses.

Brian Gormally, the CAJ’s director, quoted a provision in the Good Friday Agreement in which the British government agreed to incorporate “into Northern Ireland law of the European convention on human rights (ECHR), with direct access to the courts, and remedies for breach of the convention, including powers for the courts to overrule [Northern Ireland] assembly legislation on grounds of inconsistency.”

This, Gormally pointed out, was made in Northern Ireland law in 1998 shortly after the peace accord was ratified in referendums in both the Northern Ireland and the Republic.

Gormally added: “Any regression through changes to either the Human Rights or Northern Ireland Acts which did not meet the above commitments in the agreement would be incompatible with an international treaty.

“The European [convention on human rights] is absolutely vital in the day-to-day governance of Northern Ireland – to withdraw from it would be a colossal blow to the peace process.”

Minorities in Northern Ireland such as the gay community have also used these European human rights to battle local prejudices and political power.

Gay activist Jeff Dudgeon helped to decriminalise homosexuality in Northern Ireland back in 1981 with a landmark case in the European court of human rights. The Strasbourg judgement, the first of its kind on gay rights in the court’s history, found that his arrest for sexual activities breached Article eight of the convention, which enshrined his right to privacy. Homosexuality was then made legal in the province a year later despite opposition from the late Ian Paisley who ran a “Save Ulster From Sodomy” campaign against the law change, which was unable to block the European-led reform.

At least one gay couple resident in Northern Ireland are understood to be preparing a new case to the European court over marriage equality. The region is currently the only part of the UK where gay marriage is not recognised in law because the Democratic Unionist Party (DUP) and other unionists in the Stormont assembly have blocked moves to allow gay couples to legally marry. The couple are expected to take their case to European court and force the Northern Ireland regional government to change the law, allowing couples to marry.

The UK state has been condemned many times from the dock in Europe throughout the Troubles such as being found guilty in 1978 of inflicting “inhumane and degrading” treatment on 14 men interrogated by the British army. Successive European human rights judgments have criticised Britain over state security policy including the practice of collusion between members of the security forces and Ulster loyalist terror groups.