However, associate director at Monash University Accident Research Centre Dr Bruce Corben said at least two Australian studies showed the measure improved road safety.

The debate was prompted by the Greens and the Liberals renewing their calls for Tasmania to follow New South Wales, Queensland and Western Australia in implementing double demerit points.

Police Minister David O'Byrne said the opposing parties' calls were well intentioned but misguided.

''When you look at the data and when you look at the evidence, it doesn't actually have an impact on road safety,'' he said.

''Our belief is if people break the law no matter what day of the year it is they should be treated the same.''

He said road accidents did not increase during holidays and the government's safety campaign was working to drive down traffic fatalities.

Dr Corben said that while robust studies of double demerit schemes were hard to conduct, they had been done in New South Wales and Western Australia.

Both reported positive effects on road safety.

''Fatalities were found to have reduced during periods of double demerit points operation, as did the incidence of traffic infringements such as speeding, non-use of restraints and drink-driving,'' he said.

Dr Corben recommended a comprehensive review of their effectiveness in Tasmania be done before any decision was made.

''Personally, I favour the focus being on deterring drivers and riders from infringing, rather than attempting to catch people after they've infringed,'' he said.

In another road safety campaign, the RACT has called on drivers to dob in a ``dud road''.

RACT is compiling a list of defective roads for a 10-year strategy to develop safer roads in Tasmania.

''As holidaymakers move around the state over the Easter break they should consider dobbing in a dud road,'' chief executive Harvey Lennon said.