THE jury in the Howard Martin triple murder trial has been told it is "fanciful" to claim his three patients would have died when they did, without excessive morphine injections.

Prosecuting barrister Robert Smith, QC, said of the 71-year-old former County Durham GP's anticipated defence: "Such an argument is clutching at straws."

Dr Martin denies killing three patients by administerlethal doses of morphine.

Mr Smith yesterday made the Crown's closing speech to the jury at Teesside Crown Court. Anthony Arlidge, QC, defending, is expected to make his closing speech today, and the judge, Mr Justice Forbes, will sum up tomorrow and on Friday.

Mr Smith alleged that Dr Martin gave his three patients "thumping" doses of morphine "way in excess" of what was necessary for their treatment and did so "on a whim" only hours before they died.

He suggested that two of the seriously-ill patients were given the drugs to "help them on their way" and one - Harry Gittins, whose death sparked the police investigation - could have lived many months longer, but for Dr Martin's intervention.

Frank Moss, who had lung cancer, was visited at his home in Eldon, near Bishop Auckland, County Durham, on March 13, 2003, and was given repeated injections of morphine even though the first one left him unconscious, the court was told.

Dr Martin is alleged to have told the family of 59-year-old Mr Moss, who died early the following morning: "He is unlikely to last the night."

Five days later, Stanley Weldon, 74, of nearby Coundon Grange, was given a huge dose of morphine when Dr Martin visited him at his nursing home to treat him for pneumonia, the court heard.

The GP is alleged to have told staff: "I would have given him a little bit more if the family had not been there."

Mr Gittins, 74, of Newton Aycliffe, had been released from hospital after chemo-therapy and radiotherapy for throat cancer, when Dr Martin visited on January 21 last year.

His family wanted him to go into hospital to be treated for dehydration, but Dr Martin gave him a cocktail of injections of morphine, diamorphine and chlorpronazine at home instead, the court heard. Mr Gittins died the next day.

Mr Smith said: "This was no longer a case of Dr Martin helping a patient on his way. There was an intention to kill Mr Gittins.

"Dr Martin, for reasons we may never know, decided that Mr Gittins's life had come to an end and that he would terminate it."

Mr Smith said that Dr Martin, now of Gwynned, North Wales, did not go into the witness box to refute prosecution allegations because he had no way of answering them or justifying what he did.

He said all three patients could have been better treated with different medicine, kept comfortable and had their lives lengthened, but Dr Martin was "determined" to kill them.

The case continues.