Police investigating the death of a man in Michael Barrymore's swimming pool may have been hampered by the failure of a Home Office pathologist to spot crucial evidence, claims a lawyer for the dead man's family.
An investigation by BBC Radio's File on 4 programme has also uncovered previous cases in which the views of the pathologist, Dr Michael Heath, have been challenged by his colleagues. One case is currently being examined by the Home Office.
Dr Heath was called in after Stuart Lubbock was found dead at Mr Barrymore's Essex home last year. He concluded the 31-year-old meat factory supervisor had drowned. But three other pathologists later said marks on Mr Lubbock's forehead indicated he died of asphyxia, possibly from having an arm clamped round his throat during a sexual assault.
In the days after the autopsy, performed by Dr Heath, police assumed Mr Lubbock had died as a result of an accident. Weeks later, after the other pathologists had reviewed the evidence, two men were arrested on suspicion of murder but later released without charge. Earlier this month, the Essex coroner, Caroline Beasley-Murray, recorded an open verdict.
Now the barrister who represented the Lubbock family at the inquest, Matthew Gowen, has said the police investigation might have come to a different conclusion if the potential evidence of throttling had emerged sooner.
"The police did all they humanly could to investigate the case," he said, "but it wasn't for some weeks that they went back to Mr Barrymore's house and did a very thorough second examination. Clearly that was as a result of further reports they got as the process went on."
Dr Heath has robustly defended his findings. Legal advisers had warned him not to contribute to the radio programme but yesterday he told The Independent on Sunday: "I stand by my findings. It is not unusual for pathologists to disagree with one another. It happens all the time, but it is only in high-profile cases that it is noticed. It would be wrong for me to say that Mr Lubbock died from asphyxiation because he didn't."
Cross-examined at the inquest, Dr Heath said he had seen no petechiae, small haemorrhages that suggest asphyxiation, on Mr Lubbock's face, and stood by his belief that he had drowned.
Chris Milroy, professor of forensic medicine at the University of Sheffield, performed a second autopsy on Mr Lubbock in June last year. He found petechiae on the dead man's forehead, as did two other pathologists.
Mr Lubbock had severe anal injuries consistent with a violent assault, and cocaine and ecstasy were also found in his system. Professor Milroy said the combination of these two factors with the haemorrhages suggested that whoever caused the injuries could have done so with one arm around Mr Lubbock's neck, causing him to choke.
Mr Lubbock's father, Terry, was upset by suggestions in media reports that his son had died in an accident at a party where he had consented to gay sex. "I knew absolutely there was no way Stuart would have consented or taken part willingly in anything like that. People say he was a bit naive to go up there but I think he was attracted by the big star syndrome," he said.
The programme also reveals another case in which Dr Heath's findings have been disputed. Steven Taylor, a traveller, spent 10 months on remand facing a charge of murder after Dr Heath said he had strangled his wife. But two other pathologists said marks on Beatrice Taylor's neck were caused by procedures carried out by a mortuary technician. One said he believed she had died of an overdose of amphetamines.
In a further case a man called Kenneth Fraser was accused of killing his girlfriend after Dr Heath said she had been hit on the head with a piece of wood. He was released after four other pathologists concluded she had hit her head while falling downstairs.
The Home Office said it had received two complaints. The first, about the Steven Taylor case, was found to be groundless. A second, the subject of which it would not confirm, was still under examination.
The File on 4 programme will focus on a crisis in the forensic pathology profession made worse by growing workloads and a shortage of new recruits. Essex police did not want to comment on suggestions they might have been able to press charges if they had known sooner about the possibility of Mr Lubbock having died of asphyxiation.
'File on 4' will be broadcast on Tuesday at 8pm on Radio 4