An unimpaired motorcyclist has been suspended and fined for drug-driving after tests found traces of cannabis in his system from four days earlier.
The conviction comes as an expert warns that the ACT drug-drive regime is unjust, expensive, and breaches the human rights of Canberra motorists.
The ACT Magistrates Court on Tuesday heard that the 22-year-old motorcyclist had been knocked from his motorcycle in a minor accident at a roundabout in Crace last year.
He suffered no serious injury, but took himself to hospital on police advice where he was treated for concussion.
A blood test at the hospital was positive for THC.
But the man told the court that he had smoked cannabis four days earlier and had not been impaired at the time of the accident.
Special Magistrate Maria Doogan told the man that did not absolve him of the offence.
ACT drug-driving laws take a zero-tolerance approach, which means, unlike drink driving, the level of driver impairment is not measured.
The university student said he would not have attended hospital had he known he would be tested.
He told the court he no longer smoked cannabis and had his "life together".
Ms Doogan fined the man $700, disqualified him from holding a licence for nine months, and ordered he pay court costs.
The man is the second motorcyclist to come before the ACT courts this month on drug-drive charges after being involved in an accident.
The man – who remains in a wheelchair five months later – escaped conviction.
The territory's drug-driving laws were introduced in 2011 in a bid to manage the dangers of drivers getting behind the wheel while high on drugs.
The regime enables police to conduct random drug tests through an oral fluid test, followed by a confirmation blood test.
Blood tests are also taken after accidents.
Canberra-based social scientist David McDonald, an expert in drug-driving laws, said the zero-tolerance method had been superseded by an impairment-focused approach in many European countries, including England.
The English model operates in the same way drink-driving laws measure the impairment of a driver.
"When the legislation was introduced into the ACT, there was only limited evidence about what levels of drugs in the body cause significant impairment in driving but there has since been more research," Dr McDonald said.
"What that means is the ACT approach is badly out of date and doesn't reflect what contemporary science tells us about how to legislate for drug driving.
"In my views, based on the worldwide experience, the ACT legislation is unjust, it is not cost effective, and it breaches human rights."
Dr McDonald said there's no evidence that the laws made safer roads by reducing the number of crashes or fatalities.
He said the current regime had proven expensive in terms of police time and equipment, but warned it would cost even more to upgrade to an impairment model.
"But the expense does not justify a bad law.
"The bottom line with human rights is people are being convicted of a driving offence when there's no evidence they were impaired and were a danger on the road."