Roadside drug tests – There's no simple solution to this complex issue

Substance-impaired driving is a real concern for road safety, but the Drug Foundation has urged the government to listen to the evidence before acting on calls for random roadside saliva testing.

Public submissions have closed on the Ministry of Transport’s discussion document, and we have made our position clear: The focus should be on impairment, not just detection, and we should avoid the temptation of a quick-fix solution.

Implementing random roadside saliva testing would satisfy the calls for action, and keep the public happy – for now. But it's just not as simple as that.

We’ve said it before, and we’ll keep saying it: we don’t have the technology to employ effective roadside drug tests. Current saliva-based drug tests do not establish impairment. They are not 100 percent accurate, and they only identify a few specific drugs – which don’t include synthetic cannabinoids.

Many drugs and medications, both legal and illegal, impact driving ability. But just because a drug can be detected, does not mean the driver is impaired.

The fact is, other drugs are harder to identify and assess than alcohol. Compounding that, the effect on driving ability can be much greater when any drugs are taken in combination with alcohol or other substances.

So what is the answer? Well it’s complicated. All tests have their limitations, so we favour a multi-faceted approach. It’s important to look beyond testing and enforcement, to make drivers more mindful of safety and create lasting behavioural change.

Any debate should be about impairment not just use, and it should put the science front and centre. Our submission to the Ministry of Transport (PDF, 356 KB) sets out our position in more detail.

Our recommendations:

• That the focus for substance impaired driving should be on impairment.
• That all substances, including medications, that can cause impairment need to be targeted.
• That substance impaired driving requires a multi-faceted approach.
• That oral-fluid testing devices, while having the potential for identification of some substance impaired drivers, are not supported as the basis for random testing at this time.