The judge in the case of Pc Andrew Harper has taken the unusual step of addressing “controversy” over the jury’s decision to find three teenagers not-guilty of murder, amid concerns they were being subject to “improper pressure”.

It came after Pc Harper’s widow, Lissie, called on the Government to order an unlikely retrial in the hope of getting a murder conviction.

Henry Long, 19, and 18-year-olds Jessie Cole and Albert Bowers are being sentenced for manslaughter, having been cleared of murder.

Addressing the court on Friday morning, the judge Mr Justice Edis said: “These verdicts have caused some controversy.

“I have deliberately avoided reading or viewing reports of the case and comment on it, because I have a duty to do justice in accordance with the law and the evidence which I have heard.

“However, I have been made aware that there has been some discussion about the trial and, in particular, the measures which were in place for the protection of the jury.

“It may be believed in some quarters that the jury was subject to some improper pressure.

“To the best of my knowledge and belief there is no truth in that at all.”

The verdicts were met with anguish from the 28-year-old victim’s widow, who said she was “utterly shocked and appalled” at the decision not to convict the teenagers of murder, adding: “I now have my own life sentence to bear and believe me when I say it will be a lot more painful, soul destroying and painful journey than anyone facing a meagre number of years in prison will experience.”

Lissie Harper, has since called on the Government to intervene, despite a retrial being both extremely unusual and unlikely.

In an open letter posted on her Facebook page on Tuesday evening, Mrs Harper wrote to Boris Johnson, Home Secretary Priti Patel and former Labour Home Secretary Lord (David) Blunkett urging them and others “to right such a despicable wrong for our country”.

She wrote: “I implore you to hear my words, see the facts that are laid out before us, and I ask with no expectations other than hope that you might help me to make these changes be considered, to ensure that Andrew is given the retrial that he unquestionably deserves and to see that the justice system in our country is the solid ethical foundation that it rightly should be.

“Not the joke that so many of us now view it to be.”

It is almost exactly a year since Pc Harper and his colleague Pc Andrew Shaw responded to a report of a stolen quad bike from a property in Stanford Dingley, Berkshire, on the night of August 15 2019.

It was four hours after his shift was due to finish, though the pair were in the area so wanted to help.

They soon came nose-to-nose with the thieves towing the £10,000 Honda quadbike in Admoor Lane, prompting Pc Harper to get out of the police car and chase Cole, who had unhooked the rope between the Seat Toledo getaway vehicle and the stolen Honda.

Cole dived into the Seat, past Pc Harper’s grasp, prompting Long to make off at speeds of 42.5mph, carrying the stricken policeman behind for 91 seconds.

His uniform was stripped away and he was found by colleagues unconscious and barely alive in Ufton Lane near the A4 moments later.

Despite attempts to save him, he died at the scene.

The getaway vehicle was later tracked to the nearby Four Houses Corner caravan site.

Following his arrest, Long – who later admitted manslaughter – concocted a false alibi that he had been watching the racing film Fast And Furious at the time.

But an examination of mobile phone data eventually placed all the defendants – members of the travelling community – in the Seat.

Their defence claimed the incident was a “freak event” that none of them could have planned or foreseen.

But the prosecution said at more than 6ft and weighing 14 stone, the defendants must have been aware Pc Harper was being dragged to his death.

A fourth defendant, Thomas King, 21, from Basingstoke, had admitted conspiracy to steal a quad bike and is also due to be sentenced at the Old Bailey, before Mr Justice Edis.