Roadside drug testing is also currently very limited in the number of drugs that it can detect. Synthetic cannabinoids are not likely to be covered, nor is GHB, which we know potentially impairs somebody's ability to drive. We also know from the Australian experience that while substances may register in somebody's system, that person may not in fact be impaired. So too, over 200 medications prescribed in New Zealand come with warnings about potential for impairment, but nearly 65 percent of New Zealanders are unaware that it is illegal to drive under impairment by medication.