Three teenagers who killed Pc Andrew Harper in the line of duty as he responded to a late night burglary have been given 16 and 13-year jail terms, as the judge ruled out the suggestion jurors cleared them of murder due to “improper pressure”.

Henry Long, 19, and 18-year-olds Jessie Cole and Albert Bowers, were acquitted of murder at the end of their Old Bailey trial earlier this month, prompting the victim’s widow Lissie Harper to appeal to the Government for a retrial.

The teenagers were sentenced at the same court on Friday, where Long – the getaway driver in the vehicle which dragged Pc Harper to his death down a winding country road last August – was handed a 16-year sentence for manslaughter.

Cole, who sprinted past the outstretched grasp of Pc Harper to climb into the getaway vehicle as it made off, was jailed for 13 years for the same offence.

Similarly Bowers, also a passenger on that fateful night, was jailed for 13 years.

Sentencing the trio, who are members of the travelling community, Mr Justice Edis said: “Nothing which I can do, or could have done, if there had been a conviction for murder, can restore Andrew Harper to his loving wife and family or to the public he served so well.

“His devastating loss in these terrible circumstances will follow his family forever.”

He described them as “young, unintelligent but professional criminals”.

The judge also took the unusual step of addressing “controversy” over the verdicts.

...you killed a talented and brave young police officer who was going above and beyond his duty in order to provide a public service, you did so because you have deliberately decided to expose any police officer that got in your way to a risk of death.

He said: “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 judge added: “In better language, you killed a talented and brave young police officer who was going above and beyond his duty in order to provide a public service, you did so because you have deliberately decided to expose any police officer that got in your way to a risk of death.”

Mr Harper’s family were present in court as the sentences were handed down. Some members of the jury also returned, to an adjoining courtroom, to follow the proceedings on videolink.

Addressing the court in person, Mrs Harper broke down as she described her future being “robbed” by the teenagers.

She said: “They took more than one life away that day, they stole the person I used to be.

“I will spend every day for the rest of my life with a hole that will never be filled.”

She added: “Four weeks was all I had with my husband – four weeks to be called his wife.

“My life often feels bleak, hopeless, irreparable.”

Prosecutor Jonathan Laidlaw QC told jurors the case involved the “senseless killing of a young police officer in the line of duty, a young man who was doing no more than his job”.

The original trial was abandoned the day the country went into lockdown in March, while extra security measures were ordered for the retrial, which started on June 23, amid fears of potential juror intimidation by supporters of the defendants.

And a female juror was discharged just a day before the remaining 11 started deliberating on their verdicts after she was seen by a prison officer to mouth “Bye boys” to the teenagers in the dock.

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.”

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

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, from Paices Hill, Aldermaston, Reading, dived into the Seat past Pc Harper’s grasp prompting Long, of College Piece in Mortimer, to make off at speeds of 42.5mph, carrying the stricken policeman behind for 91 seconds.

Bowers, of Windmill Corner, Mortimer Common, Reading, was in the passenger seat.

Pc Harper was found by colleagues unconscious and barely alive in Ufton Lane near the A4 moments later, his uniform stripped from his body.

He died at the scene, despite attempts to save him.

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, now 22, from Basingstoke, had admitted conspiracy to steal a quad bike and was sentenced to two years at the same hearing.

Speaking after the case, Thames Valley Police Detective Superintendent Stuart Blaik said Pc Harper’s death highlighted the constant risks and dangers that police officers face while on duty.

He said: “What (the incident) has done is highlighted the dangers that police officers face up and down the country.

“We accept that policing is a risky business and there are always risks involved in confronting criminality, but this should never have happened.”

He said the force would review risk management around such incidents.