Karen Pettifer, of Cross Bay Road, Southampton, was clocked travelling at 58 kph along South Shore Road, Warwick on the morning of July 8 last year.

Ms Pettifer, a Canadian, was travelling to work on a black Peugot cycle when she was spotted by a traffic officer. She pleaded not guilty to the charge earlier in Magistrates' Court.

In court yesterday, Pc. Ferdinand Thorne said that he saw Mrs. Pettifer travelling towards him and estimated her speed to be between 55 and 60kph.

"I was operating a pro-lazer unit,'' Pc. Thorne said.

"I aimed the lazer at the front light of the motorcycle and released the beam and got a reading of 58 kph.'' Pc. Thorne said he relayed this information to another officer further down the road.

Pc. Thorne insisted he identified the vehicle by its registration plate number and a brief description of the vehicle.

The second officer, Pc. David Ward, confirmed that he was told the registration number of the speeding motorcycle and was able to stop Pettifer and issue her with a speeding ticket.

But Pettifer argued the first officer had failed to pass on detailed information about which vehicle was to be stopped and that a case of mistaken identity had taken place.

She told Senior Magistrate Will Francis that, as she was pulled over, she heard the words "the bike behind the white car'' being issued to Pc. Ward.

"As I was being stopped I could clearly hear Pc. Ward's radio,'' she said.

"The words "the bike behind the white car'' were repeated four times. At no time was anything else said -- only that description was offered. I then asked the officer how he could possibly identify me just from those words and he failed to answer me.

"I find it unbelievable that I could be stopped on that description alone. I heard it once and as I was trying to ask the officer a question he asked me to be quiet because he was still trying to get an identification.

"It was obvious to me by the number of times that it was put over that this was the sole evidence. There's no confidence they stopped me as the person caught in the lazer because the identification should not be accepted.'' Both officers claimed that they identified the vehicle through the registration plate number. They also failed to recall the words "behind the white car'' being used.

Fining Pettifer $220, Mr. Francis said he believed that the officers had stopped the right vehicle.

He said that the lazer beams used by the Police Service were very accurate and that, other information, such as the licence plate number, must have been given by Pc. Thorne to his partner.

"You might have heard the words "the bike behind the white car'' but that could have been given as a supplementary description,'' he said.

"You said that you heard that when you were being pulled over. I have no doubt that Pc. Ward was clearly told more than what the accused heard because he must have been told something else before she was close enough to hear those words.''