A call for an inquiry into Anne Grigg-Booth's murderous reign at Airedale Hospital has been made by the legal team representing relatives of her victims and medical officials.

Grigg-Booth's death on Monday meant there would be no trial and therefore no official examination into the circumstances leading up to her arrest.

But this week relatives of the night matron's victims called for a public inquiry into the circumstances which allowed her to escape detection for two years.

Rick Armstrong, chief executive of solicitors McKay Law, in Leeds, acting on behalf of the relatives, said he had sent a letter seeking a public inquiry into practices at the hospital to Health Secretary Patricia Hewitt.

He said there were serious concerns that action to prevent Grigg-Booth's over-prescribing had not been taken earlier. The Health Secretary has the power to order a public inquiry under the 1977 National health Act. Unlike an independent inquiry, a public inquiry could lead to a recommendation for criminal prosecution.

Health bosses have also launched an independent inquiry into the case.

West Yorkshire Strategic Health Authority (WYSHA), in conjunction with Airedale NHS Trust, launched the inquiry this week. Its findings will be made public.

A WYSHA spokesman said: "The inquiry will look into issues raised by both the trust's internal investigation and a police investigation, which led to a 52-year-old nurse being charged with three charges of murder, one charge of attempted murder and 13 charges of administering noxious substances."

The spokesman said the independent chairman of the inquiry, which will include panel members from outside organisations, and its terms of reference would be announced in due course. The terms will be agreed by the WYSHA, which will receive a report including any recommendations at a public board meeting.

Adam Cairns, Airedale NHS Trust's chief executive, said procedures had been tightened at the Steeton hospital since the Grigg-Booth investigation and he was confident Airedale was safe.

"We welcome this opportunity to have the independent inquiry so that we can ensure that all the lessons, both for us and wider NHS, can be learned," he said.

Bradford coroner Roger Whittaker announced this week that he had spoken to detectives investigating the case and asked to examine the papers. He is expected to apply to the Lord Chancellor for the authority to conduct inquests into the victims' deaths.