Police have been slammed for prosecuting an innocent motorist who "completely drenched" an officer by driving through a puddle of rainwater.

Driving instructor Tahir Mahmood was charged after creating a "tidal wave" which completely covered PC Anthony Ellison.

His actions prompted a court case which cost thousands of pounds.

But he was cleared by magistrates, who decided he was not guilty of driving without reasonable consideration after a two-hour trial.

Mr Mahmood, 33, of Briar Hill Close, Blackburn, who faced a large fine and points on his licence, said the case was a waste of taxpayers' money.

Retired police officer Kevin Delaney, head of traffic and road safety at motoring organisation the RAC, said the police had made a mountain out of a molehill.

But police defended the decision to prosecute and said it had nothing to do with the fact the person who was soaked was a policeman.

Mr Mahmood said he hoped the case would not prevent him taking up a new career -- in the police!

After the case, he said: "I apologised to the officer on the day and I have apologised to him again today. I just didn't see him until it was too late.

"It has cost me money by not being at work and it has cost the taxpayers money, so nobody has won."

Mr Delaney, formerly head of traffic with the Metropolitan Police, said: "In 30 years as a police officer I never saw a case with these circumstances go to court.

"It highlights people's perceptions that it is 'one rule for them and one for us.'

"Police have made a mountain out of a molehill.

"If I had gone to a police station to report being splashed they would probably have advised me to forget about it and send the man the dry cleaning bill."

Blackburn magistrates were told that PC Ellison was on traffic duty close to Ewood Park on the afternoon of a match between Blackburn Rovers and Tottenham Hotspur on November 29.

PS John Rigby told the court he was driving in the outside lane in Bolton Road, behind Mr Mahmood's Renault Clio.

"The Clio drove straight through the puddle," said PS Rigby. "It didn't brake or slow down and this caused what I can only describe as a tidal wave. It was that big the spray went over the top of the officer's helmet and completely covered him."

PC Ellison said he knew nothing of the approach of the car until he was "completely drenched." He tried to take the car's registration number before being told on his radio that PS Rigby had stopped it further down the road.

Mr Mahmood said he had been looking in his wing mirror for an opportunity to move into the outside lane and it was too late to take evasive action or brake.

Daniel King, defending, said the scene of someone being wet through by a passing vehicle was a sitcom classic and is part of the current Ford Focus TV advert.

"Clearly it is not funny for the victim," said Mr King. "It's not funny at all if you end up with wet trousers as the officer in this case did."

PS Stuart Isherwood, of Eastern Division Road Policing Unit said: "There is case law and people have been prosecuted successfully in the past.

"It is irrelevant whether it is a police officer or not."

"The charge is based on whether the driver could have moved out of the way of the puddle if he had been taking considerable care and consideration.

"In this case it was obviously found that he could not."