The trial of a detective garda charged with dangerous driving has been told by his defence counsel that he was not over the alcohol limit when he was involved in a collision on the M50.

Detective Garda Kevin Keys of Mountjoy Garda Station has pleaded not guilty to charges of dangerous driving and the unauthorised taking of an unmarked garda car on 6 February 2010.

On 2 February this year, the court heard evidence from Garda Keys' colleague, Sergeant Mike Smith, that Garda Keys drank about six pints of lager on the day of the incident.

Defence Counsel Dara Robinson today told the court that Garda Keys was absolutely not over the alcohol limit when he was involved in a collision on the M50.

Mr Robinson said that the Prosecution was trying to cast a whiff over the case, and that there was no charge of drink-driving.

He added that if the prosecution had wanted to say Garda Keys was intoxicated, they should have prosecuted that charge.

Mr Robinson said that Garda Keys had repeatedly told interviewers from the Garda Ombudsman Commission that earlier that day he had only consumed 4-5 lager shandies along with coffee and water.

The court also heard evidence from Garda Anthony Kelly of the Garda Forensic Collision Investigation Unit, who examined the scene of the crash.

Garda Kelly said marks at the scene indicated the ABS in the garda's Ford Mondeo may have failed. He said this was later confirmed by data from the car.

Garda Kelly said this would have caused the wheels to lock when the driver applied emergency braking.

But Garda Kelly also said he estimated Garda Keys' speed as at least 95km/h in a section of the motorway which had a 60km/h limit.

He said if a lower speed had been used, emergency braking would not have been needed.