There is a lot of red flag waving over drug driving at the moment. The problem with all these results however is that they don't necessarily imply that because someone has marijuana in their system that it means that their impaired enough to impact on their driving ability.
Marijuana can stay in the system for weeks and months, because someone tests for it, it doesn't mean that they are impaired by it. If we allow road side drug tests we will start arresting people who are testing for marijuana but who are not impaired, this then becomes a drag net being set up to arrest marijuana users.
Some in society will say good, that marijuana is an illegal drug and if you test for an illegal drug you must be punished. But if that illegal drug is not impairing ability then we are punishing for the sake of punishment.
It's a similar thirst for prisonlust that is driving the desire to drug test beneficiaries. Simply because someone tests for marijuana, doesn't mean they are impaired enough to not work, we end up punishing beneficiaries not because they can't do the job, but because they may have smoked a joint in the weekend.
What advocates of stronger rules against stoner drivers will need to do is set an impairment level if they don't want this to become a drag net for every marijuana user in NZ.
Marijuana is our most widely used illegal drug and it can stay in the system for periods of time well beyond it's impairment effect. To start a witch hunt for a substance that is illegal for the weakest of justifications could end up arresting thousands of NZers and causing far larger harm than it is supposed to be curing.