Bill Mathews had a heart attack. At the hospital, his wife was told he was brain dead. She agreed his kidneys could be removed.

Preparing to operate, the transplant surgeon saw the "dead" man move…

Polly Scott tried to kill herself with a drug overdose. In the ambulance, she could hear and see, but couldn't move. At the hospital she heard herself declared "dead on arrival."

The doctors thought that Dave Churchill was brain dead. Yet he was conscious and aware of what they were doing. Only after further tests did the doctors realise Dave Churchill seemed dead because of a drug they had given him….

Bill Mathews, Polly Scott and Dave Churchill are all Americans. They are alive and well today and they told their extraordinary stories during a special BBC "Panorama" program.

"Panorama," probably the BBC's most important current affairs show, investigated the way British doctors decide whether a person is actually dead. The program outraged the medical establishment, though it also revealed divisions among British doctors about the method used to decide whether a patient is dead.

Bill Mathews failed the tests and the doctors told his wife that her husband was dead. She agreed his kidneys could be removed for possible use in transplant surgery. Then she went home to prepare her husband's funeral.

Meanwhile the transplant surgeon arrived at the hospital to remove Bill Mathew's kidneys. As he was preparing to operate, he glanced up and saw that the "dead" man's Adam's apple was moving. Several hours later, Bill Mathews was breathing without the aid of a respirator. His wife received a phone call at home telling her that her husband was alive.

We can understand that a doctor might make a mistake about whether someone was going to recover or not – whether he was really dead. And we can accept, once that wrong diagnosis has been made, that efforts to save him will cease, and his life will be ended.

What is unacceptable is that that should happen as a prelude to organ donation – and that's what the controversy surrounding the "Panorama" program is all about.

Before any patient becomes an organ donor, doctors have to be absolutely certain that he is dead.

There is a desperate shortage of, for instance, kidney donors in Britain, and earlier this year, the Health Minister Mr. Jenkins launched a "multi-organ donor card" scheme. Television and sports personalities like footballer Kevin Keegan and England cricket captain Ian Botham appeared in advertisements telling the world that they carried donor cards.

Kidney transplants have saved the lives of thousands of people in Britain and, despite increasing criticism of heart transplants, the two hospitals doing them here are determined to continue their programs. But the "Panorama" program raised serious, even frightening, doubts about whether some of the donors in Britain are actually dead when surgeons remove their organs.

There can be little doubt that thousands of potential organ donors decided, after watching the program, not to carry donor cards and that's what has upset the medical establishment.

Today, respirators can keep a patient going so that his heart continues to beat. But his brain may already be dead, so the patient will never recover. If he really is "brain dead" then it won't be long before his heart stops, despite the respirator and all the techniques of medical science.

So where's the problem? Why not wait till that happens? Well, no hospital wants to fill the scarce beds in its intensive care units with patients who are actually dead. So it's perfectly proper to try to find out as soon as possible if a patient's brain is dead. Pressure for an early diagnosis of brain death comes form the transplant team.

The trouble is, once the patient's heart stops he's no longer any use as a potential donor. So the transplant surgeon must find a way to remove organs before a patient's heart stops.

The "Panorama" program investigated whether it is possible to diagnose death when the heart is still beating.

At the prompting of the transplanters, Britain's Royal colleges of medicine have endorsed a code of practice which asserts that brain death equals the death of the individual no matter what the heart is doing. The code also includes a series of tests that will enable a doctor to decide whether the brain is really dead. If it is, then the respirators can be switched off and, if the patient is a donor, the organs can be removed.

Earlier this year, two doctors from Papworth Hospital, where their colleagues are pushing ahead with heart transplants, wrote to the British Medical Association's journal doubting the whole concept of "brain death." It was, they said, " a legal fiction," a device to enable a doctor to say that someone was dead when he was still dying.

And according to the "Panorama" program, Bill Mathews, had he lived in Britain, would have had his kidneys removed while he was still alive.

The program also described a two-year study carried out in nine US hospitals which showed that of 165 patients who met the clinical criteria for brain death, 14 survived.

So, are British doctors actually "killing" patients who've been certified as brain dead when they aren't dead at all? Incredibly, Britain has carried out no survey of the way its medical profession diagnoses brain death despite the doubts cast on it by American studies.

Professor Bryan Jennett, of Glascow University and an authority on brain death, described the "Panorama" program as "highly irresponsible." "The public has to be protected," he said.

"Now they have been seriously misled. There has been a steady increase over the years in organs available for transplant.

"But we are worried about how many people will be prepared to donate organs after this irresponsible program."

But another brain specialist, Dr Ronald Paul, said he would not be happy to be an organ donor when brain death was diagnosed on the present system used by British doctors. He said he would only become a donor if a test which can detect brain activity even when the clinical signs of life are absent was part of the procedure for determining whether a patient was dead.

Transplant surgery saves thousands of lives and needs to be supported. But when surveys show that two in every 100 people in Britain are being labelled dead when they could make a full recovery, there is cause for concern.