Police concerned about drugged driving, use tests to show level of marijuana impairment

WSBT 22 photo

Michigan voters approved recreational marijuana earlier this month, but it won't be the law for a few more weeks.

The state's Board of Canvassers will certify the votes next week.

If everything moves as scheduled, recreational marijuana will be officially legal on December 6.

Michigan police are getting ready for that change.

They say drugged driving has always been illegal but fear it will become a bigger problem.

Police have tests to determine if someone is impaired from marijuana.

It's essentially using the same sobriety tests they use for alcohol, like standing on one leg or touching your nose.

There are other tests they can do to see if your impairment is from smoking pot.

“Blood tests are unnecessary and a poor way to determine a person’s behavior,” said Rick Thompson. “It’s those observational issues, those real physical tests that determine if someone is impaired.”

That's why Michigan State Police drug recognition expert Robert Lindsay says officers will be using those field tests to see if someone is impaired by pot.

This includes following an officer's finger or counting to 30 while your eyes are closed.

Rick Thompson from the National Organization for the Reform of Marijuana Laws says unlike alcohol, marijuana can be detected in blood without it impairing someone.

“A person who may have consumed cannabis several days ago might still test positive for the presence of cannabis,” said Thompson. “That does not indicate they were using their automobile in an impaired way.”

Lindsay says that's because marijuana breaks down into two metabolites: one makes you high (Delta 9 THC) and the other (Carboxy THC) remains in the system.

That's why they'll be looking for current impairment.

“Somebody who smoked two of three days ago is not going to be arrested based on smoking marijuana three days ago,” said Lindsay.

Lindsay says people may feel high for two to three hours but impairment can last a full day.

“You have basically a 24-hour gap where you could be impaired by cannabis whether you know it or not,” said Lindsay.

He says a new oral fluid test was just piloted that will help back up what officers see in the field.

“We would put it in the machine, and after about five minutes it would print out a result,” said Lindsay. “Then we were able to look at the result and analyze and match it up to our findings, what we saw on the road.”

Thompson says they are concerned with that type of testing. He says they need officers to take people off the road that are impaired.

They don't want to see false tests or unproven equipment used to determine this.

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