Stephen Port was sentenced in 2016 to life in prison for the murder of four men he met via the dating app Grindr. Port called an ambulance for his first victim, and left the next three in the same churchyard near his flat in the London borough of Barking between July 2014 and September 2015. Despite the similarities between the killings, police initially failed to link them, and rebuffed claims from the force’s own LGBT advisory group that a serial killer was on the loose. By the time he was caught, Port had drugged and raped eight other victims, who survived.

At an inquest on Friday, Metropolitan Police Commander Jon Savell rejected claims “that the men’s sexuality played a part in our response,” the Independent reported. However, Savell did say that his officers had a “lack of awareness” about the dangers of the date rape drug GHB and its use by gay men.

Lawyers representing the families of Port’s victims earlier accused the police of failing to properly investigate the murders due to “institutional homophobia” within the force, something Assistant Commissioner Helen Ball denied.

“We don’t see institutional homophobia, we don’t see homophobia on the part of officers, we do see all sorts of errors in the investigation which came together in a truly dreadful way,” she told the inquest.

Some of these errors, the inquest heard, included the police neglecting to search Port’s laptop for 10 months, during which time he killed his second and third victims. When an officer finally did search the computer, he failed to register Port’s interest in rape pornography as suspicious. The inquest also heard how the Metropolitan Police’s major investigations team declined to take over the case from local officers in Barking and Dagenham, who themselves had failed to notice a previous rape claim against Port.

Detective Inspector Tony Kirk, who led local policing in Barking at the time of the murders, said that his officers dealt with “hundreds of crimes every day,” meaning complex investigations had to “take a back seat.”

Speaking through his lawyer after the inquest, Ricky Waumsley, a partner of one of Port’s victims Daniel Whitworth, called on Metropolitan Police Commissioner Cressida Dick to resign. “Ricky is shocked to hear the extent of the police incompetence,” the lawyer told reporters. “Ricky continues to believe that there was police prejudice during the investigation.”

Whitworth’s father called the police’s investigation “abominable,” and told Sky News how "time after time after time, from top to bottom in the Barking borough, the performance of the police has been inexplicable.”