The UK's controversial Troubles Legacy Act would face a legal challenge filed by the Irish government on Wednesday (December 20).
Dublin's opposition stemmed from the law giving an amnesty to alleged murderers during The Troubles, the 30-year conflict in Ireland marked by violence and lawlessness that took over 3,500 lives and left thousands seriously injured.
Ireland's lawsuit was filed under the European Convention on Human Rights, the BBC reported.
Separately, victims and survivors of The Troubles have already taken Westminster to court in the High Court in Belfast.
Last September, British Northern Ireland Secretary Chris Heaton-Harris said that passage of the bill marked a "significant milestone as the government aims to deliver on our pledge to deliver better outcomes for those most affected by the Troubles while helping society to look forward."
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The bill was introduced by former British Prime Minister Boris Johnson in 2021 in a bid to "draw a line" under The Troubles, including bringing an end to all new inquests and civil actions related to the conflict, which Dublin vehemently opposed.
"This decision was taken after much thought and careful consideration," Irish Deputy Prime Minister Micheal Martin said in a statement. "I regret that we find ourselves in a position where such a choice had to be made."
He also said that the British government "pursued legislation unilaterally" despite the concerns of the Irish government and other stakeholders.
"We are not alone in our concerns," Martin added. "Serious reservations about this legislation have also been raised by a number of international observers, including the Council of Europe's Commissioner for Human Rights and the UN High Commissioner for Human Rights."
Martin further claimed that the law was "opposed" by people in Northern Ireland, a region where the UK still holds the island as its own.
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