A Shropshire woman lost control of her car at least 50 metres before a head-on crash with a vehicle on the other side of the road which resulted in the death of a friend, a court has heard.

Shrewsbury Crown Court also heard yesterday that 19-year-old Kirsty Williams, of Baldwin Webb Avenue, Donnington, Telford, had under-inflated tyres, which could have contributed to a loss of steering control.

Williams denies causing the death of 17-year-old college student Jonathan Humphreys, of Baschurch, who was a passenger in her car, by dangerous driving.

Mr Humphreys died after Williams’s Vauxhall Corsa collided with a BMW shortly before 1pm on January 30, 2008, in Huffley Lane, near Bomere Heath.

Williams, who was a student at Walford College at the time, had driven four friends into Shrewsbury to get a McDonald’s and they were on their way back.

Constable Neil Williams, an accident investigator, arrived at the scene of the accident at 1.11pm.

He told the jury about a number of marks and gouges left on the road as a result of the crash and said it appeared the Vauxhall Corsa was out of control at the time of impact and tyre scuffs showed it had been out of control for 54 to 55 metres.

Mr Francis Laird, prosecuting, said: “The tyres were under-inflated for the weight being carried.

“What is the effect of under-inflated tyres on a motor vehicle?”

Mr Williams replied: “The steering will become less precise and unpredictable in the sense of what you are used to.

“Under-inflated tyres are more likely to cause an under-steer, it does not steer as quickly as you wish.

“My opinion is that the vehicle speed into the bend, the steering of the driver and the under-inflation of the tyres would contribute to the loss of control.”

The jury was told the damage showed the Vauxhall was at least 60cm onto the wrong side of the road at the time of the collision and had swung into a verge before crossing the white lines.

The court also heard that the owner’s handbook for a Vauxhall Corsa recommended the pressure of the front tyres be 35 pounds per square inch and the back tyres 41 pounds per square inch with a full load.

The Vauxhall Corsa’s back tyres were 28 and 29 pounds per square inch and the remaining front tyre was 28 pounds per square inch. The other was deflated.

The trial continues.

By Rhea Parsons