Independent inquiries into killings by mentally ill people would cease to be mandatory under draft proposals commissioned by the Department of Health.

A leaked draft of a report by HAS 2000 ranks investigations into 'serious and untoward incidents' - including homicides - into three categories: routine, standard and special.

'Special' or fully independent inquiries would only be held in the 'relatively rare event' that cases were deemed to have a 'serious public interest' or could offer 'major national lessons'.

'Standard' homicide cases and some other serious incidents would be examined by a permanent panel described as a multi-agency serious incident group for which health authorities would have lead responsibility.

This would include representatives from social services, mental health trusts, primary care groups, the police and probation departments. It would report regularly to regional offices, the Commission for Health Improvement and the Social Services Inspectorate. Local managers would be allowed an 'element of discretion' in deciding which cases should be examined by the group.

Incidents judged to be 'routine' would be dealt with internally.

The proposals are due to be passed to the DoH this month, but have already met with a mixed response.

Managers have supported an end to 'a culture of blame' under which 'costly and bureaucratic' independent inquiries 'wheel out the same lessons again and again'.

NHS Confederation policy manager Janice Miles described current processes as 'very bureaucratic and legalistic, and very costly with most of the money spent on lawyers'.

'Their conclusions are often very similar - there isn't an awful lot new that comes out of them.'

In the past five years, 65 inquiries have reported and another 25 are pending, with the costs ranging between£70,000 and£1m each.

Mind policy director Melba Wilson said: 'They all bring up the same issues - that there is a need for better risk assessment, for professionals to talk to each other, for shared information and better care planning.'

But the Zito Trust and Sane expressed concern. Sane chief executive Marjorie Wallace said 'to do away with independent inquiries is like throwing away the black box after a plane crashes'.

Michael Howlett, chief executive of the Zito Trust, flagged up a 'problem of accountability' when decisions to refer investigations to an independent level relied on the 'discretion' of local managers.

'I don't really see what the motivation is for any local manager in the NHS to refer a case on for fuller inquiry, ' he said.

The proposals were formed by an expert panel, including chief executive of the Mental Health Act Commission William Bingley and psychiatrist Professor Louis Appleby, director of the National Confidential Inquiry into Suicide and Homicide by People with Mental Illness.