As cannabis laws relax across North America, you might be wondering if there is anything you should know before you smoke weed and drive yourself. Maybe you've heard friends say that they drive better while under the influence of cannabis; touting that it makes them drive slower and pay more attention. Admittedly, there isn't much data on whether cannabis has had an influence on driving practices on the road, but it's always best to operate a motor vehicle when you're stone sober. For your convenience, we've listed what you should know before you smoke weed and drive.
1. Smoking marijuana impairs your driving ability to some degree, but just how much it impairs it depends on your personal tolerance and the strain of cannabis you consumed. You should know that simulations and real driving tests have shown that smoking weed and driving negatively impacts a person's reaction time, memory, motor coordination, visual functions, one's perception of speed, and attentiveness.
2. Impairment from smoking marijuana heightens when paired with alcohol, even that one drink with dinner.
3. Smoking weed and driving is illegal, just like drinking and driving. Most states have a zero-tolerance stance when it comes to using cannabis behind the wheel, but Colorado and Washington have set a legal THC threshold in blood levels of five parts per billion. However, since traces of psychoactive compound tetrahydrocannabinol (THC) can stay in a cannabis user's system for days (or weeks) after the herb was consumed, blood tests are an imperfect method for measuring someone's current state of marijuana-induced impairment. We don't yet have a standard roadside test (like a breathalyzer) for detecting if someone is under the influence of cannabis, but some law enforcement agencies are experimenting with a way to test saliva samples.
4. If you are pulled over, prepare to be questioned and take a field sobriety test, possibly paired with a breathalyzer to rule out alcohol use. Law enforcement officers look for signs of impairment such as bloodshot eyes, slurred speech, and poor motor skills, as well as any drug paraphernalia (like pipes or papers) or the odor of marijuana. Depending on how you do, you may or may not be detained.