MORE than 90% of The Northern Star's online readers support changing drug-driving laws, according to an informal poll.
But the Centre for Road Safety's general manager, Marg Prendergast, denies motorists are being wrongly convicted of drug driving due to flawed legislation.
The laws were criticised by Lismore solicitor and drug law reform author Steve Bolt in an article published on Monday, because drug testing did not measure intoxication levels.
Police testing only measures an active presence of cannabis, speed, ice and ecstasy, which can be detected while a person is not intoxicated by the drugs.
Ms Prendergast said more research was needed into how drug use affected driving and at what level.
"It is not clear what specific amounts of these drugs lead to what level of driving impairment, as this can vary by the drug used, the combination with other drugs, including alcohol, and factors to do with the individual," she said.
Despite issues with pinpointing whether a driver is affected at the time of driving, Ms Prendergast defended the current legislation.
Ms Prendergast said about half of drug-driving offences were drivers charged for having drugs present in their system, rather than being impaired behind the wheel.
She dismissed Mr Bolt's call for drug-driving laws to mirror drink-driving laws.
"While there is a threshold for alcohol, it is important to note that alcohol is a legal drug and the Centre for Road Safety recommends that if people are planning to drink at all, then they plan not to drive," she said.
Local courts have accepted some motorists charged with driving with an active presence of cannabis had taken the drug more than 24 hours before they were tested.
Meanwhile, Bangalow-based Hemp Foods Australia founder Paul Benhaim said he understood police were concerned industrial hemp food could interfere with roadside drug-testing methods if made legal to eat.
This was despite it containing miniscule and inactive properties of cannabis's psychoactive compound THC.