A police chief has denied “systemic” errors in the investigation into the death of Barking serial killer Stephen Port’s first victim Anthony Walgate.

Ch Superintendent Andy Ewing, who has since retired, was Barking and Dagenham Borough Commander at the time Mr Walgate was murdered by Port in June 2014.

Mr Walgate, a 23-year-old fashion student from Hull, was found dead outside Port’s flat in Barking on June 19 that year after being given a fatal dose of the drug GHB.

Port alerted emergency services anonymously, claiming to be a passerby, then lied to investigators when they tracked him down.

Within hours of Mr Walgate’s body being found, Mr Ewing was briefed that Port had a previous allegation of sex assault against him, according to a note in his day book.

But the intelligence from the police national computer did not come to light as part of the investigation until nearly a week later, jurors were told.

Giving evidence at inquests into Port’s four victims on Monday, October 25, Mr Ewing accepted there were errors in the investigation, but denied they were systemic.

Asked about his notes, Mr Ewing said: “I cannot comment on where the information came from.

“That information should have been included in any assessment of the situation at an early stage.”

Days later, Mr Ewing was copied into an email by acting Det Ch Insp Tony Kirk appealing for the case to be taken over by a murder investigation team.

Mr Kirk wrote there was a duty to get to the bottom of what happened in “what are increasingly suspicious circumstances”.

He told senior colleagues that “on the balance of probability, Anthony died at the hands of another”.

Mr Ewing told jurors that the dispute over primacy had been “unprecedented”.

Andrew O’Connor, counsel to the coroner, asked: “Did you think then, or do you think now, it was surprising (that) the decision was primacy would not be taken over for this case?”

Mr Ewing replied: “I really cannot recall what I thought at the time around the issue of primacy.”

Jurors heard he went on to write in an email that he was “really unhappy” about the system of work.

He stated: “My position on this is that we push for a PIP3 accredited SIO (senior investigating officer) whenever there is any possibility of a homicide – not just ask for advice.

“We do not have such detectives on borough.”

Mr Ewing told jurors that he could not recall why he sent that email.

When toxicology results for Mr Walgate came back, a detective inspector asked a sergeant to refer the case back to the homicide team, jurors heard.

Neither of them made the referral and the sergeant eventually closed the investigation, the inquest was told.

Mr Ewing said he could not comment on the matter, as it was the first time he had heard about it.

Mr O’Connor pressed him, saying: “You were at the top of the tree.

“We see the requirement being placed on you to ensure a functional effective CID unit was in place.

“That failing – or apparent failing – together with others does suggest there was not a functioning CID unit in place at the time.”

Mr Ewing replied: “I accept there were errors that were made but I am struggling to see how that is a systemic failure which was part of my responsibility and statement of expectation.”

The inquest heard how the investigation took place amid budget cuts and reduction in staffing numbers, with more officers acting up in senior positions.

But Mr Ewing insisted that Barking and Dagenham Borough CID unit remained generally “fit for purpose”.

Port was convicted of perverting the course of justice in relation to Mr Walgate. He also killed Daniel Whitworth, Gabriel Kovari and Jack Taylor.

Dr Anton van Dellen, who represents Mr Whitworth’s partner, asked: “Do you, as the most senior officer on borough at the time, accept any personal responsibility for those string of failings?”

Mr Ewing said: “Having reflected on this for many years and having looked at the material available to me, I believed the actions I took at the time were appropriate.”