A police driver who knocked down the Channel 4 newsreader Sheena McDonald was on the wrong side of the road, a court heard yesterday.

Glenn Whiteley, 27, a constable with the Metropolitan police, pleaded not guilty to driving without due care and attention when he appeared before Horseferry Road magistrates, London.

The accident happened last February near Miss McDonald's home in Islington, north London, when Whiteley was answering an emergency call with a colleague. One witness said the police van had been travelling fast but had slowed before it hit Miss McDonald, 44, who was crossing the road.

She suffered brain injuries and was in a coma for 72 hours, remained in intensive care for two weeks, and needed treatment for a further two months.

Helen McCormack, prosecuting, said Whiteley found his path blocked by stationary traffic, so drove on the other side of the road, travelling in the wrong direction.

The van's sirens and flashing lights were on, but Whiteley's colleague warned him the pedestrian was looking in the wrong direction.

"His fellow police officer noted that she appeared to be looking away from the direction they were coming from," said Miss McCormack. "But PC Whiteley was later to tell an officer investigating the case that she had glanced in his direction and he had assumed that, because he had his sirens on, she would have seen him."

Miss McCormack said although he slowed, Miss McDonald was struck by the front passenger side of the van, which braked, carried on a few yards and stopped. "But it had to be reversed to free her from the van," she said.

Paulo Canaccuti, who saw the accident, told the court: "They were travelling really fast at around 40 to 45mph, I guess."

PC Malcolm Cumberlidge, an accident reconstruction specialist, said Whiteley had been driving too close to the centre of the road.

"The vehicle should have been slightly further to the right of the road, which would have been a safer distance. This would have given him more time to avoid pedestrians," he told the court.

He added that the driver was travelling at a considerable speed, but from studies of the accident it was clear he had slowed considerably at the time of the accident.

Miss McDonald will not be giving evidence, but in a statement said she had been returning from a lecture in Piccadilly, where she had drunk two glasses of wine.

The case continues today.