Pressure grows on 'fair weather' law-enforcement tool
Inconsistency in police rules for the use of laser speed guns could prompt another wave of requests from drivers for a review of their convictions for speeding, a lawyer has said.
Simon Ip Shing-hing said drivers convicted on the basis of laser gun readings obtained when it was raining would have an advantage over the prosecution if it could be proved that the bad weather had affected the readings.
'If [police] knew the results may be marred by rain and they still chose to do it, this is an enforcement mistake and those affected would undoubtedly raise an outcry,' Mr Ip said.
John Reading, deputy director of public prosecutions, said laser guns should not be used in the rain because the beams they send out would be reflected back by raindrops, and this would affect the accuracy of results.
However, a frontline police officer said the force occasionally used laser guns in light rain.
'We would judge by the road's condition - such as whether it has a good drainage system or an anti-slip coating - before deciding whether or not to carry on with the operation,' said the officer, who refused to be named. 'Sometimes the rain may go on for hours if it is only drizzle.'
The officer said the gun's accuracy would not be compromised in light rain. He did not say where he had obtained this information.
But Ringo Lee Yiu-pui, vice-chairman of the Institute of the Motor Industry Hong Kong, said such a practice was unprofessional.
'If there are official instructions that police should not [use speed guns] in rain, it doesn't matter how light the rain is. Motorists should certainly make a complaint if they ever get caught speeding in the rain.'