Julie Anne Genter says public and expert consultation over roadside drug testing is important because there are issues with the technology that is currently used.
Plans to improve drug driver testing are being opened for public consultation, after a petition calling for an urgent law change on roadside testing has been reopened this week.
Associate Transport Minister, Julie Anne Genter, told Mike Hosking she wants to canvas opinion on the issue, rather than bring in regulations immediately.
"I think it's important that we go out to the public on this and hear from the experts. I want to follow the evidence on what is going to reduce impaired and dangerous driving."
Genter said if saliva testing was introduced it would make it easier for police to test for impaired drivers.
"What this is about is using new tools, like saliva testing, so the police can do more drug driving testing and impairment testing at scale, in order to reduce the problem," she said.
However, Genter also said there have been issues with the technology used to test for drugs.
"The difficulty has been actually getting a technology that can establish impairment, that can test for the most common substances, and that can do it at a scale like alcohol breath testing. Saliva testing is still not like breath testing - it takes a lot longer."
"There are some key issues that we need to go out to the experts and the public with," she said.
She said there are a number of questions they still need to answer before making a decision.
One of which is what tolerance level there would be for drivers under the influence of drugs.
"Obviously at the moment with some substances we would have zero tolerance because they are scheduled substances that people should be taking anyway," she said.
In terms of cannabis, it's still unclear what that level would be if the drug was legalised, Genter said.
"Jurisdictions who have legalised and regulated the use of cannabis have opted for different options. Some have zero tolerance and some have infringements system that is more like what we have with alcohol. So very low levels, which are unlikely to impair, you receive a fine as opposed to a criminal penalty."
She said she wants to consult the public on the level and follow the evidence on what reduces impaired driving.
In 2018, 71 people were killed in crashes where a driver was found to have drugs or medication in their system. This is compared to 109 deaths where the driver had alcohol in their system.
The Associate Transport Minister said there is no evidence to suggest legalising cannabis will increase its use.
She said it all depends on the regulations and policies in place.
Genter has previously said that she does not want roadside testing to be introduced.