LOS ANGELES (CBSLA.com) — Drug-impaired driving is a growing problem, and a proposal to legalize recreational marijuana in California could make it worse, according to the Automobile Club of Southern California.

The Auto Club says nearly 20 percent of fatal collisions in California involves at least one driver who tested positive for drugs.

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“The problem extends beyond recreational marijuana and illegal drug usage — many prescription drugs can impair skills that are critical to driving,” said Kathy Sieck, senior vice president of public affairs for the Auto Club.

The Auto Club opposes Proposition 64, which would legalize recreational marijuana use in the state for people age 21 and older. Approval of the measure could contribute to an already growing problem of drug-impaired motorists, Sieck said.

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“Prop. 64 is a gamble on the public’s safety, which isn’t a risk worth taking, especially when drug-impaired driving is on the rise,” she said.

Proponents of the measure insist the proposal includes a requirement for an extensive public-health information campaign that will include information about the dangers of driving while impaired by marijuana “and the potential harms of using marijuana,” according to Californians for Responsible Marijuana Reform.

The group also contends the measure will provide $3 million a year to the California Highway Patrol to develop updated DUI protocols for determining when a driver is marijuana-impaired and impose restrictions on the acquisition of marijuana, including “strict safeguards against children accessing it.”

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