The senior forensics expert with West Mercia Police admitted yesterday that he could not rule out the presence of another person at the death of the hanged Telford doorman Errol McGowan.
Tristram Elmhirst, who is employed by West Mercia Police Authority as director of forensic services, said it was "absolutely correct" to say that no fingerprinting had been done at the scene, Mr McGowan's vehicle had not been examined, and protective gloves had not been used to handle exhibits.
The 34-year-old black doorman had been found hanging from a door handle in an empty house after complaining to police that he was being racially harassed and had received death threats.
At an inquest in Telford, Mr Elmhirst said he only became involved in the inquiry into Mr McGowan's death when the investigation was relaunched in February last year with "a presumption of foul play".
Peter Herbert, representing the McGowan family, said: "Where there may be foul play, what would you have expected at the scene?"
Mr Elmhirst said: "It would have been treated like a major inquiry."
Mr Herbert then asked: "There are significant amounts of forensic evidence which have been lost between the seven to eight months between the death and any new examination?" The forensic expert replied: "You would assume that would be the case."
Mr Herbert said: "Forensically you cannot exclude third-party involvement in that scene?" Mr Elmhirst responded: "You cannot include it in relation to that scene, either."
Mr Herbert said: "You are in a position of ignorance. You simply don't know." Mr Elmhirst replied: "That's correct."
Mr Herbert asked: "If the investigating officer messes it up at the time, makes an assumption that this is suicide ... and there was some forensic information at the scene, it is lost and gone for ever?" Mr Elmhirst said: "Not necessarily. It could be, yes. Certain elements."
The witness was asked if fingerprinting the scene on the day of the death would "not have been futile" as it was deemed seven months later after people had been living in the house. Mr Elmhirst said: "At the time of the finding of Errol McGowan I agree. If it is seen as being a suspicious death."
The forensics director told the hearing that the death of Mr McGowan, and later of his nephew Jason McGowan, had been "an element" in a culture-change at West Mercia Police in the way that it treated scenes of crime.
The inquest heard from Paul Millen, a scenes-of-crime expert involved in training at the National Police College in Durham, who criticised officers' actions at the scene. Mr Millen, a former close colleague of Mr Elmhirst at the Metropolitan Police, read a report to the coroner, Michael Gwynne, in which he said "too many assumptions were made".
"The assumptions were not tested, many of them could and should have been explored using forensic science," he said.
Mr Millen added that as well as carrying out fingerprinting, police should have treated Mr McGowan's car, which was parked on the driveway of the house, as part of the suspicious scene. He confirmed that he had written an article in Police Review magazine in which he had spoken of his "embarassment" at finding that the door and the surrounding wall had not been fingerprinted 10 months after the death.
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