The woman, known as Miss D, was suffering a "living death" and the time had come for "merciful relief," said Sir Stephen Brown, President of the High Court Family Division.
The case breaks new ground because in previous cases where doctors have applied to turn off life-support machines of seriously brain-damaged patients, the victims have been in a "persistent vegetative state" (PVS).
Miss D was not considered by experts to be in a PVS because she could track movement with her eyes and responded to cold water being poured into her ears.
James Munby QC, who was appointed to represent the woman's interests, told Sir Stephen that the reason the Royal College had been anxious to identify what he had called a "bright line" over which the boundaries should not be pushed was because there was always a danger of going down a "slippery slope". But the judge, in his ruling said that all the consultants, doctors, medical team and family were agreed that Miss D had no awareness of her surroundings or herself, and all the evidence was that there was "no possibility of any meaningful life whatsoever". Sir Stephen said that he did not feel he was altering the boundaries of who could be allowed to die. "I am driven to the conclusion ... that it is in this patient's best interest to withdraw the artificial feeding and hydration which is keeping her body alive."
But the judgment was condemned by the anti-euthanasia group, Alert, which said the "barbaric practice'' of cutting off life support systems to brain- damaged patients should be banned. Dr Peggy Norris, chairwoman of Alert, said: "Withholding food and fluids from a person capable of experiencing thirst had been used as a form of torture."
The British Medical Association took the view, however, that the judgment did not extend the categories of patients from whom nutrition and hydration can be withdrawn. "It is an acknowledgement that it would be ethically acceptable to consider withdrawal of nutrition and hydration from an individual who has permanently lost his or her sentience and awareness," a spokesman said.
Miss D was at university when she was seriously injured in a road accident in 1989. She recovered enough to walk round in familiar surroundings, but in 1995 was found unconscious in her bed, probably having had an epileptic fit. She has never subsequently recovered consciousness.
This week her feeding tube had become dislodged, and a small operation would have been needed to replace it. Consequently the hospital trust caring for her had applied to the court for a declaration that it was lawful to "discontinue all life sustaining treatment". Its request was upheld.
A spokesman for the Royal College of Physicians said the decision had caused confusion. "We set up a working group to produce guidelines, in order to help doctors in a difficult situation. But they are only guidelines and the judge is not obliged to follow them. The judgment does not change them, but it seems to be leading to some uncertainty among doctors."Reuse content