PC Andrew Harper was responded to a report of a stolen quad bike in August last year when he was dragged more than a mile to his death.
Three teenagers have been found guilty of manslaughter after dragging a British police officer to his death when he got caught on their vehicle.
The driver, 19-year-old Henry Long, was cleared of a murder charge on Friday but had earlier pleaded guilty to the manslaughter of PC Andrew Harper.
His passengers in the car, Jessie Cole and Albert Bowers, both 18, were also found guilty of manslaughter.
All three are now facing jail time.
PC Harper, a newlywed, was killed in August last year when he was attending the scene of a reported quad bike robbery in Berkshire, west of London.
As the 28-year-old tried to arrest the teenagers, Long drove off at 42.5mph (68km/h), resulting in a tow rope on the back their Seat Toledo entangling the officer's legs and pulling him along with them.
The officer was dragged for more than a mile behind the car and was later found by his colleagues with his uniform stripped and unconscious.
He died at the scene.
Defence counsel for Long, who was reported to have threatened to "ram" police in an incident a year earlier, argued the teenager could never have known that PC Harper had gotten caught on the car.
The prosecution, meanwhile, argued that Long must have been able to feel the officer's weight as they dragged him to his death.
Long is said to have previous convictions for battery, being drunk and disorderly and shoplifting.
Bowers, too, has previously been convicted for battery, criminal damage, sexual assault, and being in possession of an offensive weapon.
The trial was originally scheduled to go ahead at an earlier date, but was postponed due to the UK's coronavirus lockdown.
Extra security measures were also put in place for the court dates to avoid jurors potentially being intimidated by people supporting the defendants, who are said to be from the travellers' community.
In a statement, Thames Valley Police Detective Superintendent Stuart Blaik said he was "delighted" by the outcome, but stressed that no one could "ever imagine" what PC Harper's widow, Lissie, had been through.
He added: "It’s just absolutely devastating for them.
"This whole process of the court trial, having to relive what’s happened and listen in to the grisly detail of how Andrew came to his death.”