Marijuana can be had in probably every city of any size across the country, and it’s already legal for medicinal use in dozens of locations. It’s also legal for “recreational use” in Colorado and Washington state – with the federal government turning a blind eye toward the state activities.

That means there’s going to have to be, at some point, a way for law enforcement officers to determine whether people are under the influence, especially when they drive.

So ReasonTV asked for the advice of criminal defense attorney Mark Gallagher about the issue of cotton swabs being used to take samples from suspects for lab testing.

“You can refuse this swab, you can refuse a breathalyzer, you can refuse to participate in a field sobriety test, you can refuse to answer questions,” he told interviewer Tracy Oppenheimer.

He said there could be administrative penalties for that but the tests cannot be forced.

“Law enforcement doesn’t like this advice, but we do still have a Constitution,” he said.

At issue is whether swab tests will be used like blood tests are for alcohol to determine impairment.

He warned there are a number of problems.

“It doesn’t tell us when they took [marijuana], or how much they took, and how is it affecting their ability to drive the vehicle.

“And that’s really what we need to know, to know whether or not that person is a safety risk on the road,” he told ReasonTV.

He said the question at some point will end up before a court, which will have to decide whether the test is accurate, whether it’s constitutional, whether it’s reasonable, whether its invasive.

He said the reality is that officers all have recorders, dashcams and the like, and if someone is under the influence, it won’t be hard to prove.

“If someone’s truly dangerous, document it, present it to a jury. You’re not going to have a hard time convicting,” he said.

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