Drugged Driving and the Law
The relationship between drugs and driving ought to be obvious – as straightforward as the warning label on a prescription bottle: Do not drive or operate heavy machinery while taking this medication. But it’s not.
Around the U.S., the issue is how we should treat drivers who have been taking drugs (legal or illegal). The problem comes in because simply being able to detect a substance in someone’s system (which science is very good at) doesn’t tell you how impaired the person is.
Marijuana, which is detectable for a week or more after even a single exposure, is of particular concern, especially since the drug is legal for medical use in 18 states.
Some states have opted for pro se laws.
Arizona, Delaware, Georgia, Indiana, Illinois, Iowa, Michigan, Minnesota, Nevada, North Carolina, Ohio, Pennsylvania, Rhode Island, South Dakota, Utah, Virginia and Wisconsin all make it illegal to drive with any detectable amount of an illegal substance in the driver’s system.
But this seems too harsh. Drugs are detectable long after their effects have worn off. What’s actually needed is something akin to how alcohol is handled – above a set minimum, impairment is assumed, with the minimum based on testing and averaging out driving performance.
And make no mistake, Americans love to drug and drive. The National Institute on Drug Abuse, citing the National Highway Traffic Safety Administration’s (NHTSA) 2007 National Roadside Survey, reported that more than 16 percent of weekend, nighttime drivers tested positive for illegal, prescription, or over-the-counter medications. More than 11 percent tested positive for illicit drugs.
The marijuana debate
It’s not uncommon to read in the pro-marijuana community that cannabis doesn’t impair driving or that it can even make someone a better driver. For example, Paul Armentano, the Deputy Director of NORML, was quoted as saying:
There is evidence that cannabis causes changes in performance, and some of these changes may make you less likely to have an accident. For instance, you’re less likely to change lanes, so you’re less likely to have accidents occurring as a result of that. But that does not necessarily make you a safer driver. For instance, we see performance changes in braking latency, and there’s also some evidence of impairment of peripheral vision.
A study reported on in The Atlantic found a doubling of risk for an accident among those who had smoked marijuana up to three hours before driving. “There is also a substantially higher chance of an accident for motorists aged 35 or younger.”
Solving the problem
As we reported six months ago, scientists are trying to pin down the answers. But it’s slow going. Meanwhile, states that are legalizing marijuana for recreational use have to come up with an answer now.
Colorado is a case in point. Legislators there are struggling to figure out if they will set a standard blood level (measured in nanograms per milliliter) as some other states have done or figure out another method. Everyone agrees something should be done, but no one has a solution all parties find acceptable.
Advocates claim that chronic users of marijuana (as for medical purposes) will give false positives because long-time users become immune to some of the side effects of weed, including a reduced ability to drive, but still show high levels of the drug in their systems. They also point out that different cannabinoids (the active ingredients in marijuana) do not all cause impairment. In fact, this is so. Strains of marijuana that contain less THC but lots of other cannabinoids will not get someone as high as “normal” pot, but will still generate metabolites the tests detect.
Opponents of marijuana use say that without a standard in place, the courts will be clogged with cases as each defendant brings up the same issues in an attempt to avoid punishment.
Right now, a default method is in place, applicable in every state. If a police officer determines someone is driving improperly (weaving, changing lanes inappropriately, or any dangerous behavior) they can stop and arrest someone for driving while impaired – even without ascertaining a particular cause. This charge is harder to prove in court, but can be successfully prosecuted, especially when there is video evidence showing impairment.
Down the road
It’s safe to say that the ideal situation would be a roadside saliva test that could be administered quickly and generate accurate results. Such a test would find not only levels of cannabis, but also a laundry list of other drugs. Drugs on the list would include both illegal drugs and prescription medications known to cause impairment. Further, a national standard would replace the state-by-state guesswork we have now. Across the US, drivers know that a blood alcohol level over 0.08 percent will get them arrested. While the penalties for DUI vary by state, the standard is recognized and accepted everywhere.
How close are we? It’s hard to say. Even tests that measure actual performance give different results in different people. Other factors come into play as well – the age and experience level of the driver, how familiar they are with the route being traveled, and even whether they are well rested or not. In the end, it’s likely that some standard, even an imperfect one, will be better than none at all.