A MEDICAL expert has claimed a doctor accused of killing three patients should have told one of the men that the morphine injection could kill him.

Dr John Grenville told a jury that that he would have warned 59-year-old Frank Moss and his family that the drug could make him go to sleep and not wake up again.

Dr Grenville, an expert in the care of cancer patients, said that Mr Moss's GP had given him 12 times the recommended dose of morphine on two occasions in the hours before his death.

He said that the second injection could not have been claimed to be a painkiller because Mr Moss was unconscious from the first one, given seven-and-a-half hours earlier.

Mr Moss's daughter said Dr Howard Martin injected her father with a syringe that was already filled with morphine when he took it from his medical bag.

The cancer care specialist was recalled as a prosecution witness in the third week of the trial of 71-year-old Dr Martin, a retired GP who had surgeries in Newton Aycliffe, Bishop Auckland and Shildon, in County Durham.

Dr Martin, who now lives in Gywnedd, North Wales, denies murdering cancer sufferer Mr Moss at his home in Eldon, near Bishop Auckland, on March 13, 2003.

He also denies murdering patients Stanley Weldon, 74, from Coundon Grange, near Bishop Auckland, and Harry Gittins, 74, from Newton Aycliffe.

Dr Grenville told the jury at Teesside Crown Court: "I don't think that 60mgs was advisable because of the strong possibility of producing unwanted effects."

Dr Grenville said between 2.5mg and 5mg would have been appropriate as a starting point for Mr Moss, and that doses that were given were likely to kill a patient.

The trial continues