In Illinois, legal users of pot can drive legally Jan. 1, if not impaired
On Jan. 1, Illinois residents with medical cannabis cards may purchase marijuana, use it and later drive - legally.
If a card holder is pulled over, authorities must prove impairment - a different burden of proof than drivers who have illegally used marijuana; they can be found guilty of DUI through a blood test that detects any amount of pot.
"We'll rely on traditional sources of evidence, observations, statements and driving habits," Kane County State's Attorney Joe McMahon said. "Just because you have a prescription doesn't give you license to drive a vehicle if you're impaired."
Police will use standard DUI tests such as the walk-and-turn and one-leg stand to determine marijuana impairment.
But some say these field tests are designed for DUI-alcohol arrests and are insufficient to spot drugged driving; something similar to the actual blood alcohol detection tests is needed, they say.
In Illinois, the legal threshold is .08 blood alcohol concentration. Some states have similar thresholds for active THC, the primary psychoactive ingredient in marijuana.
For example, 5 nanograms per milliliter of blood is the threshold in Washington, where marijuana is legal for recreational use.
Rita Kreslin, executive director of the Schaumburg-based Alliance Against Intoxicated Motorists, said the group is neutral on the issue of medical marijuana, but wants roads to be safe.
AAIM leaders say Illinois should have a standard for marijuana impairment; they're concerned that the "subjective opinion" of an officer administering standard field sobriety tests for alcohol intoxication "may not be accepted by the courts," in cases of marijuana impairment, according to Kreslin.
Having some specific standards, she said, "would be a good place to start. It's not perfect, but it could help. It's better than having nothing at all."
But the National Highway Traffic Safety Administration says a standard may be difficult to establish.
"It is inadvisable to try and predict effects based on blood THC concentrations alone, and currently impossible to predict effects based on (THC metabolite) concentrations," according to the NHTSA's website.
Greg Sullivan, executive director of the Illinois Sheriff's Association, said the group opposes marijuana for both medicinal and recreational uses.
Ideally, officers would have access to an instant test or swab that could be used to check if THC levels are above a certain threshold, Sullivan said.
Some of these devices are used in Europe and a pilot program is underway in California, according to the safety administration.
"What is impairment for marijuana? Right now it is zero. You can't have it in your system," Sullivan said.
"We're flying blind right now. The law is what it is. We enforce the laws. If you need medical marijuana with your condition, don't drive. Play it safe."