A number of parties came under fire as the coroner overseeing the inquest into the death of spy Gareth Williams delivered her verdict.
Dr Fiona Wilcox did not hold back from levelling criticism with the Metropolitan Police's counter-terror branch, SO15, the first to be attacked.
"Those officers involved interviewed Gareth's colleagues though I know no formal statements were taken and I find that this did affect the quality of evidence that was heard before this court," Dr Wilcox said.
The handling of an Apple iPhone belonging to Mr Williams, which contained deleted images of him naked in a pair of boots, was also censured.
Detective Superintendent Michael Broster, who was responsible for SO15's involvement in the investigation, said he had seized it from the spy's workplace and kept it in his possession until the following day, when he had handed it to one of his officers.
But Dr Wilcox said: "I find this is either not what occurred - in which case how did he acquire this phone? - or it demonstrates disregard for the rules governing continuity of evidence."
MI6's much-criticised failure to report the code-breaker missing for a week after he failed to turn up to work was raised and Dr Wilcox said she could "only speculate as to what effect this had" on the investigation.
A slip-up by the forensic teams working on the case was also noted, with the coroner pointing out that "a lot of time and resources" were spent investigating a DNA sample taken from Mr Williams's hand that much later "unfortunately" turned out to belong to one of the forensic scientists.
And she suggested that whoever had leaked to the press that the spy possessed an expensive collection of women's designer clothing could have been trying "to manipulate perception of the evidence".