A senior police officer has expressed regret that he did not push harder for specialist murder detectives to take over the investigation into the death of Anthony Walgate, Stephen Port’s first victim.

Mr Walgate, a 23-year-old fashion student, was found dead outside Port’s flat in Barking, east London, on June 19 2015 after being given a fatal dose of GHB.

Port had alerted emergency services anonymously, claiming he was a passer-by, and then lied to police about the circumstances of Mr Walgate’s death.

On June 26, Temporary Detective Chief Inspector Tony Kirk emailed senior colleagues saying the force had a duty to Mr Walgate’s friends and family to get to the bottom of what happened.

The borough CID commander wrote: “Anthony Walgate appears to be organised and experienced in his activities and has a group of friends who are obviously concerned at the manner in which he has died as, I am sure, so are his parents and family.

“I feel we as an organisation have a duty to his friends and family to get to the bottom of his death in what are increasingly suspicious circumstances.”

Mr Kirk’s lawyer, Richard Atchley, asked what he was hoping to achieve.

He replied: “I hoped the superintendent and MIT (murder investigation team) would accept my rationale and take on the investigation.”

He said that did not happen and none of the people he had emailed responded.

Mr Atchley asked: “Did you feel as acting DCI you were in a position to push it further at that time?”

Mr Kirk replied: “No.”

His lawyer continued: “With the benefit of hindsight, do you wish you had done so?”

The witness replied: “Yes.”

Mr Kirk told the court that staff had been “stressed” and “overworked”, with some reduced to tears, creating an atmosphere in which errors are made.

There were mistakes in sharing intelligence with colleagues about a previous allegation against Port, not instructing a search on the police national database (PND) about him, and not sending his laptop off for scrutiny until nearly a year after he first struck, jurors have heard.

Mr Kirk had allocated an inspector to supervise the investigation, but he stepped back “almost immediately”, the court heard.

Peter Skelton QC, for the Met Police, asked if he was disappointed by that.

Mr Kirk said: “Now knowing the outcomes, most definitely.”

Mr Skelton said: “Checking that actions were completed would be a basic fundamental part of its supervision. If that does not take place, errors are made.” Mr Kirk agreed.

Mr Skelton said: “So far as the actions such as searching for PND intelligence or searching the laptop, do you have any answer why they were not completed? It appears to be human error.”

Mr Kirk said: “I do not know why they were not checked.”

The court has heard that during his 16-month killing spree Port also gave fatal GHB doses to Gabriel Kovari, 22, from Lewisham, Daniel Whitworth, 21, from Gravesend, and Jack Taylor, 25, before he was caught.

Port, now 46, was handed a whole life prison term in 2016 upon conviction.

The inquests at Barking Town Hall are looking at whether police mistakes prevented Port from being stopped sooner.

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