It is stunning that this ruling was necessary, but it does correct a ridiculous standard for guilt in DUI cases.
To be convicted of driving under the influence, the state must now prove they you were under the influence and impaired at the time of driving, and not just weeks before. Seems pretty obvious, doesn’t it? Yet before this decision, it was simply not the case.
This decision by the Arizona Supreme Court fixed a previous decision by the appeals court that the state could prosecute medical marijuana smokers for DUI even with no evidence of impairment.
The presence of a non-psychoactive compound that remains in the body and can show up in urine tests weeks after consumption does not constitute impairment under the law.
Carboxy-THC can remain in someones bloodstream for up to 30 days. Hydroxy-THC is the active ingredient in marijuana that can cause impairment, but it breaks down into non-psychoactive Carboxy-THC within hours.
This interpretation “leads to absurd results,” the high court panel wrote. “Most notably, this interpretation would create criminal liability regardless of how long the metabolite remains in the driver’s system or whether it has any impairing effect.”
Disturbingly, one justice actually dissented from this opinion, suggesting that any challenges should be addressed on a case by case basis.
Proof of Marijuana Impairment is Tricky
Some states have tried to establish a 5 nanogram of THC in the bloodstream as the equivalent standard for impairment as .08% BAC is for alcohol. But experts concede that the substances are very different. THC effects people very differently, what may impair one person could have a negligible effect on another person.
Other standardized field sobriety tests used to prove alcohol impairment in drunk driving cases should still be accurate and legal in marijuana DUI cases, although many any physical impairment caused by marijuana is different and less debilitating to physical coordination that alcohol.
There is no doubt that science and law enforcement will continue to explore and legally definite pot inebriation in some way.
Driving in a way that impairs your ability to control the vehicle, or make safe decisions behind the wheel is of course a public safety issue. And this issue isn’t going away, as use of medical marijuana expands, and the possibility for full legalization on the horizon a few years down the road.
But hopefully the legislature and courts will avoid any more crazy “zero-tolerance” rules, and adopt a more sane approach to criminal penalties that allows marijuana patients to exist.