(FOX 11) - The Anaheim Police Department hosted a forum at the convention center Tuesday to talk about motorists driving under the influence of marijuana if Proposition 64 passes.
Unlike alcohol, it's difficult to prove someone is high because there's no good test.
"There's not scientific basis for a B.A.C. equivalent for marijuana," Jeffrey Spring, Automobile Club of Southern California, said. "If someone is pulled over it may be difficult to show that they were under the influence because marijuana affects different people differently."
That's a major concern for California law enforcement if Proposition 64 passes in November. The initiative would legalize recreational marijuana in the state.
To discuss the implications, the Anaheim Police Department hosted a forum of experts to weigh in on "drugged driving."
"If anybody says legalizing more drugs makes this a safer place to drive, I don't believe they are being honest with you," John Jackson, Police Chief of Greenwood Village Colorado, said.
Jackson said there's been a dramatic increase in drugged drivers on the roads.
"For 2014 and 2015 more than 77 percent of the arrests for impaired driving involved marijuana for the state of Colorado," Jackson said.
"We're seen an increase in impaired driving with marijuana, but part of that is because we didn't start testing for marijuana until after legalization in some cases, once we hit alcohol we stopped the test," Justin Nordhorn, Chief of Liquor and Cannabis Board in Washington State, said.
Testing for marijuana on a traffic stop is difficult.
Officers can perform a field sobriety test, but testing for substances in the blood could prove false since THC can stay in your system for at least a month.
Prop 64 will help fund better testing, according to supporter Nate Bradley.
"It has funding that will go to CHP that will allow the studies to be done to modernize our DUI and impairment training because that's what's key," Nate Bradley, Ex. Dir. California Cannabis Industry Assoc., said.
On Wednesday, the Automotive Club Southern California will host another panel on the same topic at the Peterson Automotive Museum in Los Angeles.
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