The Irish government has a "moral" and "legal" obligation to take an interstate case against the UK if the Westminster government's controversial legacy Bill becomes law, a protest has heard.
Mark Thompson, CEO of Relatives For Justice, addressed families of those killed during the Troubles, who gathered with signs and pictures of their loved ones outside the Northern Ireland Office in Belfast.
"What we want the Irish government to do is to take an interstate case against the UK to Strasbourg," he said.
The Northern Ireland Troubles (Legacy and Reconciliation) Bill proposes an effective offer of immunity from prosecution for perpetrators of crimes during the Troubles who co-operate with a truth-recovery body.
It would also halt future civil cases and inquests relating to the conflict.
Strasbourg is the home of the international court of the Council of Europe, which interprets the European Convention on Human Rights (ECHR).
States can lodge applications against each other in the European Court of Human Rights under article 33 of the ECHR.
In the Dail on Wednesday, Taoiseach Leo Varadkar said the government would "give consideration to whether an interstate case is appropriate".
Speaking at the protest on Wednesday, Mr Thompson said the Irish government had a moral and legal obligation to take the case under the Good Friday Agreement.
"We are now saying to the Irish government, to Leo Varadkar and Micheal Martin, the diplomatic channels have not worked. You need to set out now the mechanism by which and how you will take the case to Strasbourg," he said.
"You need to do it. This society needs you to do it. All victims of all persuasions are opposed to this. You will be taking in the interests of every single victim across these islands, and throughout this entire jurisdiction you will be taking that.
"You have a moral and legal duty to do that under the Good Friday Agreement as well.
"This Bill not only flouts international law, the European Convention on Human Rights and the Human Rights Act, it also flouts the Good Friday Agreement itself because the Human Rights Act is an essential component of that agreement."
He added: "We're speaking up and with one voice. We're asking the Irish government: do the right thing. Go and take the case on behalf of every single victim. You have a duty to do it."
Previous interstate cases have been taken in relation to the Troubles. For example Ireland took an interstate case against the UK in relation to interrogation techniques used in Northern Ireland from 1971 to 1975.
The legacy Bill has been opposed by victims groups and all Stormont parties, as well as the Irish government.
The Bill is currently in the report stage in the House of Lords.
Mr Thompson said the legacy legislation denied bereaved families the right to an investigation.
"So just to make it clear, this Bill is anti-rule of law, anti-victim, anti-Good Friday Agreement, anti-international human rights law," he said.
"It denies the right to a basic investigation and truth and accountability.
"That's all that families have been wanting for decades since their loved ones were killed, and their tenacity and never-giving-up spirit to go on is amplified again and again and again."
Sinn Fein MLA Gerry Kelly attended the protest on Wednesday.
"The families here will never give up, they will keep fighting on in the courts, but also it's up to the Irish government, to take on their behalf - they're Irish citizens - to take on their behalf an interstate case to the British government to try and destroy this," he said.
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