The sentences given to three teenagers for the manslaughter of PC Andrew Harper will not be changed after the Court of Appeal dismissed challenges by the Attorney General and the trio.

The Court of Appeal ruled today (December 16) whether PC Andrew Harper's killers' sentences for manslaughter are "unduly lenient" following a bid by the Attorney General to have them increased.

READ MORE: 'I will not stop until I see change in our systems': Lissie Harper responds to decision NOT to change sentences of killers

Henry Long, 19, was sentenced to 16 years and 18-year-olds Jessie Cole and Albert Bowers were handed 13 years in July over the death of the Thames Valley Police traffic officer.

Pc Harper, 28, was caught in a strap attached to the back of a car driven by Long and dragged to his death down a winding country road in West Berkshire as the trio fled the scene of a quad bike theft on the night of August 15 2019.

Announcing the Court of Appeal's decision, Dame Victoria Sharp said the court had dismissed the Attorney General's appeal against Long, Cole and Bowers' sentences for manslaughter, as well as the trio's own appeals against their custodial terms.

The court did reduce the sentences imposed on Cole and Bowers for conspiracy to steal, from 38 months detention to an 18-month detention and training order given their ages at the time of the offence.

READ MORE: Court of appeal to rule on PC Andrew Harper killers' sentences

However, Dame Victoria said: "The effect of our decision is that all three offenders remain convicted of the manslaughter of PC Harper and the overall length of their custodial sentences remain unaltered."

An application by Cole and Bowers for leave to appeal against their convictions for PC Harper's manslaughter was refused as being "wholly unarguable".