A judge described a staff nurse who murdered four elderly patients and tried to kill another as a thoroughly evil man, as he jailed him yesterday for at least 30 years.

Colin Norris, 32, from Glasgow, killed the vulnerable women with massive doses of insulin while working at two hospitals in Leeds in 2002.

The prosecution suggested that Norris, whose demeanour in court appeared arrogant, was motivated by a dislike of geriatric patients.

Sentencing him at Newcastle Crown Court, Mr Justice Griffith said that he had considered imposing a full life term with no hope of early release.

He said: “You are, I have absolutely no doubt, a thoroughly evil and dangerous man. You are an arrogant and manipulative man with a real dislike of elderly patients. The most telling evidence was that observation of one of your patients, Bridget Tarpey, who said ‘he did not like us old women’.”

The judge said that Norris was an essentially lazy man who believed that the elderly simply required too much care. He said he was certain that Norris had not been intending any kind of mercy killing, because none of his victims was terminally ill.

“I suspect you enjoyed the power that ending a life gave you, choosing the elderly because they were defenceless,” said the judge.

Norris was convicted on Monday of killing Doris Ludlam, 80, Bridget Bourke, 88, Irene Crookes, 79, and Ethel Hall, 86, while working at the Leeds General Infirmary and St James’s Hospital. He also attempted to kill Vera Wilby, 90, but she survived the insulin-induced coma.

All were frail, elderly women who had been admitted to the orthopaedic ward at one of the two hospitals after suffering hip fractures.

Detectives, who considered 72 cases altogether, are convinced that the serial killer was stopped in his tracks and would have gone on to claim more victims. There are questions surrounding the deaths of three more patients.

Norris, who showed no emotion in a packed court, was given four life sentences and 20 years for attempted murder. He was told that he would have to serve a minimum of 30 years before being considered for parole.

The Leeds Teaching Hospitals NHS Trust has said that changes have been made to improve patients’ safety on the wards. However, Dr Hugo Mascie-Taylor, the medical director, acknowledged that no procedures could have stopped the determined criminal.

After the hearing Stuart Hall, 53, the son of Ethel Hall, said that the families would like an independent inquiry into the murders.

He said: “I do not understand why Colin Norris pretended to be a caring nurse when he was really a cold-blooded killer who preyed on the vulnerable he should have been caring for.”

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