A volunteer group of pot smokers got together to get high under the watchful eyes of law enforcement.
Recreational marijuana is legal in California, but officers say driving under the influence of the drug is a big problem on the road.
"Approximately 75 percent of the DUI arrests that I make nowadays are drug impaired, more cannabis than alcohol," Glendale Police Officer Bryan Duncan said at a "green lab" held recently in Orange County.
The group of smokers gathered at a hotel where they were given field sobriety tests and then were allowed to toke up. Later, they took the tests for a second time to judge how their mental and motor skills were affected.
"Whether it's a lack of convergence in the eyes, divided attention issues, your ability to do two tasks at one time," Duncan said to KCBS-TV.
And indeed, there were some stumbles in the toe-to-heel walk and some off-target responses to being asked to hold your finger to your nose.
Chris Halsor ran green labs in Colorado, after that state became one of the first to legalize recreational pot use. He is now helping California, which decriminalized personal use in 2016, to help officers establish public safety criteria.
"I think we have some detection tools that are out there. There are a lot of questions [about] do we need better tools out there," said Halsor, founder of Understanding Legal Marijuana. "The science is severely lagging behind the policy, because it is still illegal federally."
The volunteers wanted to show officers that individual reactions can vary greatly.
"It's different for everyone," said user Sebastian Dominguez. "If you're an avid user, it is going to affect you differently."
But he doesn't advocate smoking and driving.
Neither does volunteer Edson Villegas. "If I'm high, I don't want to drive," he said. "Like why? If I'm high, I just want to sit there."