A retired doctor has been struck off after giving excessively high doses of morphine to 18 dying patients.
A disciplinary panel found that former County Durham GP Dr Howard Martin had not acted negligently but had "violated the rights of the terminally ill".
He was cleared of murdering three of his patients five years ago.
But he has been struck off by the General Medical Council (GMC) for "completely unacceptable" treatment of some patients.
The fitness to practise hearing in Manchester centred on the deaths of patients between 1994 and 2004 at surgeries in Newton Aycliffe, Shildon and Eldon.
It heard that Dr Martin had an "autocratic attitude" and believed he was always right.
It also heard that while some of the 18 patients might have had only days or hours to live, the deaths of some could have been hastened.
In the case of Harry Gittins, 74, there was also a possibility that he could have gone on to recover from oesophageal cancer had Dr Martin not intervened and administered 200mg of diamorphine on the day before he died.
He also wrongly told Mr Gittins' family that his cancer had spread, the hearing was told.
GMC panel chairman Professor Brian Gomes da Costa said: "Dr Martin's decisions to administer large doses of strong pain-killing drugs were made on the scantiest of evidence.
"There were many occasions when there was no clinical indication that the patient was suffering any pain.
"His record-keeping, including reasons for giving treatments, was appalling."
Dr Martin did not attend the hearing, and in a letter from his solicitor he said he had no intention of doing so as he did not intend to practice again.
In 2005, he was found not guilty of murdering patients Frank Moss, 59, Stanley Weldon, 74, and Mr Gittins.