Doctors can lawfully stop treating a 20-year-old man who suffered a brain injury after a fight in a pub garden, a High Court judge has ruled.
Specialists say roofer Andy Casey's brain stem function has died and he is therefore dead.
Mr Justice MacDonald, who oversaw a private trial in the Family Division of the High Court in London on Friday, said on Tuesday he agrees.
Hospital trust bosses responsible for Mr Casey's care had asked the judge to rule treatment can lawfully end, but his relatives want it to continue and say they have seen movement and signs of life.
Mr Casey's sister, Christine, 27, told the judge she does not believe he is brian-stem dead.
After the ruling, she said she is "so angry" and relatives aim to appeal.
Ms Casey said the judge had looked at video footage showing Mr Casey moving.
"He reacts to pain," she said. "I showed the judge so many videos. How can someone who reacts to pain be dead?
"We are looking at an appeal."
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A lawyer representing the hospital trust, which has responsibility for Mr Casey's treatment, asked the judge to rule it would be lawful to cease artificial ventilation and care.
Barrister Abid Mahmood said brain stem testing by two specialists showed Mr Casey is dead.
He told the judge in a written case outline that Mr Casey had been involved in a fight in a pub garden on 9 July and was "punched to the head" and "fell to the ground". He said specialists had diagnosed death on 16 July.
The judge heard Mr Casey had remained on a ventilator since being injured.
In a written ruling, Mr Justice MacDonald said: "Whilst I understand fully the conclusions that the family and friends of Mr Casey have, in their sorrow, drawn from his movements and apparent responses to the ventilator, having regard to the totality of evidence before the court, I am also satisfied that what the family are seeing are in fact well-recognised base reflexes that can survive brain stem death.
"Cruelly, the flattering voice of hope convinces those that love Mr Casey that these are signs that Mr Casey is not dead.
"With regret, I am satisfied that the brain stem testing undertaken... demonstrate(s) that he is."
'A tragedy' for family and friends
Mr Justice MacDonald said he had concluded, with "very great sadness", Mr Casey "died on 16 July 2023 at 11.51pm".
He added: "I understand that this will come as a bitter disappointment to Mr Casey's family and friends.
"The now blurred boundary between life and death can be delineated by reference to philosophy, to ethics or to the cardinal tenets of the world's great religions.
"But the task of this court is to consider whether Mr Casey has crossed over that boundary for the purposes of the law."
He said he is satisfied, having regard to brain stem testing undertaken in accordance with a code of practice, Mr Casey had died.
The judge added: "I recognise that this is a tragedy for his family and friends and whilst I am certain that it will offer little comfort, they have my profound sympathy."
Well-wishers have pledged nearly £11,000 to a GoFundMe appeal organised by Ms Casey, which says the money raised will "help to cover legal costs" and "rehabilitation" if Mr Casey "pulls through".