'Medical advances have made a profound difference'

Dame Elizabeth Butler-Sloss, president of the High Court Family Division, said such cases were the "most difficult" judges had to consider.

She told a conference in London the area was "a minefield".

But Dame Elizabeth said the law could "provide a way forward" and set limits on what treatment was appropriate.

It is often the role of the law to set limits on what is and is not appropriate Dame Elizabeth Butler-Sloss

She recently presided over the case of baby Luke Winston-Jones, whose parents opposed doctors' views that their child should not receive life-prolonging treatment.

Luke suffers from a rare genetic disorder. Dame Elizabeth gave permission for doctors to withhold life-saving treatment by mechanical ventilation if his condition deteriorated.

In another recent case, a judge ruled baby Charlotte Wyatt should not be revived if she stopped breathing again, siding with the views of doctors.

Charlotte weighed just one pound when she was born 14 weeks prematurely with serious heart and lung problems, but her parents wanted her to have every chance of life.

'Expectations transformed'

Dame Elizabeth, who was speaking at the Withholding Treatment conference in London organised by the Royal Society of Medicine and the Disability Rights Commission, said there was "no quick fix" to deal with such difficult cases.

She added: "Cases where the court has been asked to decide whether live-saving treatment ought to be administered are often the most difficult cases a judge will ever have to deal with, not because the law is confused or difficult but because of the emotions of the people involved in the case."

Dame Elizabeth said innovations in medical science had changed the social landscape almost beyond recognition.

"From birth until death, and most things in between, medical advances have transformed our expectations.

"Life-saving, life-prolonging technologies have made a profound difference to the treatment options for the terminally ill."

Dame Elizabeth said that, given such possibilities, there would inevitably be diverging views as to the appropriateness of some treatments.

"Doctors sometimes disagree with patients and their relatives, and patients themselves may disagree with their family and friends.

"It is often the role of the law to set limits on what is and is not appropriate."

Parliament 'catching up'

She said the "best interests test" was the benchmark in all cases that considered the withholding of treatment, and the role of judges was to set boundaries and reach a resolve when the different parties, such as families and doctors, could not agree.

"Everybody who is involved has their own views on what is in the best interest of the individual.

"It is the role of the judge to draw those views together to resolve the conflict in those views and provide a way forward."

Dame Elizabeth said the Parliamentary process was slow and often in a process of catching up.

"It has therefore become the role of judges to develop the law and give liberal interpretation of the statute when circumstances demand it.