A police investigation must be carried out into claims internees - known as the Hooded Men – were tortured in Northern Ireland in 1971, the Court of Appeal in Belfast has ruled.
The 14 men were held without charge at British Army facilities in Ballykelly, Co Londonderry during the Troubles.
Surviving members argue authorities failed to comply with duties under the European Convention on Human Rights to properly probe and order a full inquiry into what happened to them.
They say they were subjected to interrogation techniques including hooding, being put in stress positions, being forced to listen to white noise, and being deprived of sleep, food and water.
The European Court of Human Rights previously ruled that, while the men suffered inhumane and degrading treatment, it fell short of torture.
However, delivering the majority ruling at the Court of Appeal, Lord Chief Justice Sir Declan Morgan said the treatment of the men “would, if it occurred today, properly be characterised as torture”.
Two of the three judges were satisfied with that conclusion, while one dissented.
The court therefore found that the PSNI must investigate the treatment of the men, dismissing the Chief Constable’s appeal against a previous High Court judgement that its decision to end preliminary inquiries into the methods deployed was seriously flawed and should be quashed.
One of the Hooded Men, Francis McGuigan, welcomed the ruling.
Speaking outside court, he said: “We are delighted with the result we got this morning.
“Justice Morgan confirmed Justice Maguire’s decision that, if this happened today, it would be torture - I would just like to know how they differ between today and 48 years ago when they use the word torture.”
Mr McGuigan added: “It’s a small word, but let me just give you some of the impact it had on me as a 23-year-old of average intelligence - what they had done to my brain and my body, I finished up that I couldn’t spell my own name.
“They asked me to spell my own name and I couldn’t spell my own name.
“I think Europe made a mistake then, and I want to stand in front of the judges in Europe and tell them what happened to me and the rest of us.”