If you ever feel like overdosing on euphemisms, I advise doing time with the mental health lobby. This is something I have done on and off, out of journalistic interest. These people do heroic work with sufferers, and campaign to highlight their needs. But their determination to stamp out stigma can lead them to rewrite reality. Illness has become health. Patients have become clients. Savage attacks on other people have become “untoward incidents”. Now last week’s devastating inquiry into the death of 50-year-old Denis Finnegan, murdered while cycling through Richmond Park by a paranoid schizophrenic, John Barrett, is being twisted by powerful groups who put patient “rights” above public protection.

A respected consultant psychiatrist neatly summed up his profession’s hostility to inquiries. “Being retrospective,” he said, “they foster a simplistic notion of the preventability of homicides”. Really? What last week’s inquiry showed was that Finnegan’s death was wholly preventable, caused by gross incompetence and arrogance — from the tribunal that discharged Barrett in the absence of his doctor, to the psychiatrist who gave him an hour's leave from hospital, to the nurses who failed to warn the right people that he had not returned.

Once again — and I am a bit of a connoisseur of these inquiries — we read of “cumulative failure”. An innocent person is hacked to death by someone with clear warning signs: in this case, violent voices in his head. But the psychiatrists always know better.

The Barrett inquiry is crystal clear: the South West London and St George’s Mental Health Trust, which “cared” for him, is incapable of putting its own house in order. Yet the trust blithely issued a confident statement last week about improvements already made. The whole reaction has been surreal. On Friday the Royal College of Psychiatrists insisted that “all the professionals involved in this inquiry [must] be supported” and announced that it is planning — a seminar. Shouldn’t someone be sacked? No. I can find only one example of a psychiatrist resigning after a murder inquiry, and that was in 1997.

The Mental Health Alliance, a group of 80 charities, is concerned only to emphasise that Finnegan’s death was “extremely rare”. This is a familiar refrain from those who fear the public will shun schizophrenics. But it borders on falsehood. When I called the Department of Health this week, I discovered that between 55 and 63 people are killed every year by people who have recently been in contact with mental health services. At about 10 per cent of the total murder count, dare I say this is quite a lot?

The charity SANE believes that at least one in three of those murders is preventable. Its analysis of 69 such inquiries finds that in half the cases, professionals had ignored warnings from family and friends. Some psychiatric patients refuse treatment. What is less well known is how many others are denied it, even when they or their relatives are crying out for it.

The Barrett inquiry vividly describes the culture that seems to be endemic among the lunatics running our asylums. “Too much confidence,” it finds, “was placed in clinical judgments unsupported by evidence and rigorous analysis.” There was a preference for “engaging” with patients, over “intervening”. There is an understandable reluctance to act in loco parentis for adults who may at times be perfectly capable.

But the jargon of “empowerment” creates nonsenses. It means a manic depressive choosing not to “engage” with social services, which then walk away. It means a schizophrenic choosing whether or not to take medication, even if he has a violent history. It means setting Barrett free to buy a packet of knives and take a taxi to Richmond Park. In most cases, treating people who have lost their reason as though they were rational beings leads to misery and neglect. In a few cases it leads to death.

Last Friday, the Government launched proposals for community treatment orders (CTOs). These would compel formerly detained patients who pose a risk to the public to take their medication or return to hospital for treatment. A vast lobby is massing against this. The Mental Health Alliance is comparing CTOs to ASBOs, and muttering about human rights. But they will only apply to a small number of potentially dangerous individuals. They could provide greater stability for people who are on the misery-go-round between prisons, hospitals and the “community”. The lobby makes much of the Barrett inquiry’s finding that the problem was not lack of legislation. But the inquiry does support CTOs.

Compulsion is tricky territory. But that does not justify selective deafness about the findings of such an important investigation. The light that such processes shine may explain why there is now a concerted effort under way to circumvent them. Finnegan’s brother was originally offered an internal review by the mental health trust, and told he would have to sign a confidentiality contract to read it. It was only with the support of the Zito Trust, one of the sanest charities, and John Reid, then the Health Secretary, that he got an independent inquiry.

Others have not been so lucky. Haringey Primary Care Trust has just completed an internal review into the case of Ismail Dogan, who stabbed six people in North London in 2004, killing one. His mother had appealed for help after he had stopped taking his medication, but got none. Will Haringey publish?

We cannot get away from what happened to Denis Finnegan by giving it another name. It was murder, and someone needs to take responsibility for it.

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