A policeman who drove through red lights and killed a mother-of-two has had his driving ban reduced.

PC Nicholas Andrews-Faulkner, 45, was disqualified from driving for four years after a Winchester Crown Court jury convicted him of careless driving but cleared him of causing Karen Stagg's death by dangerous driving.

Andrews-Faulkner, of Sweetlands, Hassocks, was fined £2,000, had nine points endorsed on his licence, was banned from the road for four years and ordered to take a further driving test before he can get back behind the wheel.

Mr Justice Mackay, in London's Appeal Court, cut the driving ban yesterday to three years and set aside the order for a further test. The licence endorsement order was also overturned.

Mrs Stagg, 47, died in January last year. Her car was passing through a green light at a junction near Gatwick airport when it was hit by Andrews-Faulkner's police car.

Also in the car with Mrs Stagg was her 12-year-old son, Philip, who was injured.

The officer, who had a previously exemplary driving record, claimed he was distracted by the antics of an unruly prisoner in the car, who needed to be controlled.

Mrs Stagg's husband, Graeme, 61, was test-driving a BMW just in front of her at the time of the crash and was confronted by the full horror of the tragedy.

In a witness statement read to the crown court he described watching the collision and seeing his wife "fade away in front of my eyes".

Andrews-Faulkner's counsel, David Jubb, today rebutted suggestions from Mr Stagg that the officer did not do enough to help in the crash's aftermath.

The barrister said: "That's not a true reflection of the position."

He added that his client had been in a "state of shock" in the immediate aftermath, later carrying out emergency resuscitation.

But Mr Justice Mackay said the trial judge had pinpointed one particularly worrying feature of the case - the PC's "Inability to explain why the accident happened".

The lights had been red against Andrews-Faulkner for some time before the crash, the court heard, and although his police role entitled him to pass through them, he had to do so "with appropriate care" and give precedence to those relying on the green light.

The trial judge had described it as "more than a momentary lapse of concentration", describing the officer's conduct as "one of the worst cases of careless driving" likely to reach court.

But Mr Justice Mackay said the officer's driving had not fallen so far below the standard of a reasonably prudent police driver, otherwise the jury would have convicted him of a more serious charge.

In those circumstances the four-year ban was excessive, said the appeal court judge, substituting the three-year ban.