California Weed

Recreational marijuana is legal in California, but stoned driving is still hard to detect

‘Being under the influence is about impairment’

Highway Patrol officers learn how to conduct sobriety testing at the CHP Academy in West Sacramento, including ways to detect how drivers are impaired by marijuana.
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Highway Patrol officers learn how to conduct sobriety testing at the CHP Academy in West Sacramento, including ways to detect how drivers are impaired by marijuana.

When a 22-year-old Hayward man allegedly slammed his Cadillac into a California Highway Patrol vehicle containing Officer Andrew Camilleri on Christmas Eve, he was under the influence of alcohol and marijuana, officials said.

Camilleri, who lived in Tracy with his wife and three children, died in the crash.

CHP reported that Mohammed Abraar Ali had a blood-alcohol level of .11, above the state limit of .08 for motorists. While it’s not clear how the agency documented Ali’s cannabis consumption, he said he got high at a Christmas party, authorities said.

Proving intoxication from weed is more difficult than it is with alcohol, as law enforcement does not have a device like a breathalyzer for alcohol. Without such a tool, law enforcement must rely more on roadside sobriety tests.

These are the same tests used for drunken drivers: walking a line and tracking the movement of an officer’s finger, among others. While CHP officials say the tests have been effectively used to detect stoned drivers for years, experts have pointed out that some judges and prosecutors are less comfortable with the subjectivity of them.

For public-safety officials, Camilleri’s death heightened concerns about the dangers of driving under the influence of marijuana, in part because it happened just days before California started allowing retail cannabis sales to adults 21 and over. The death revived calls for stronger laws governing stoned driving.

Officials from the CHP and the state Office of Traffic Safety have said they worry that legalization will lead to an increase in stoned driving, pointing to statistics in Colorado that showed an uptick after the state allowed recreational marijuana sales in 2014.

But California for now will not be able to precisely measure if retail marijuana sales have the same effect because CHP doesn’t distinguish between marijuana and other substances when arresting suspects for drugged driving.

Several states, including ones that legalized marijuana before California, have sought to toughen stoned driving laws by setting limits on the amount of THC that can be in the body. THC is the psychoactive compound in marijuana. Similar proposals have so far been unsuccessful in California.

Thomas Marcotte, who is leading research into stoned driving at the University of California, San Diego, cautioned lawmakers against taking that approach until research and technology catch up.

“Right now, I don’t think the science is there to back it up,” said Marcotte, a researcher at the school’s Center for Medicinal Cannabis Research.

Without an approved breathalyzer for marijuana, police sometimes use blood tests. But they have not been proven reliable, and some suspects have been found to have low levels of THC despite obvious signs of impairment, Marcotte said.

Conversely, other suspects who regularly consume marijuana may have large amounts of THC stored in the system, yet display little or no signs of impairment, Marcotte said.

The National Highway Traffic Safety Administration and transportation associations have reached a similar conclusion about laws based on THC limits.

Such laws “imply a relation between drug concentrations and impairment. The scientific consensus is that the evidence to establish these relations does not exist,” according to a 2017 report by the Governors Highway Safety Association.

Without an established measurement for marijuana impairment, law enforcement agencies have relied on a program to train officers in how to evaluate signs of stoned driving. The program was started by the Los Angeles Police Department in the 1970s before it was taken over by the International Association of Chiefs of Police and NHTSA. The program trains officers to become experts in recognizing the symptoms of a range of drugs.

To become a drug recognition evaluator, officers must take a 72-hour class taught by CHP. About 1,700 drug recognition evaluators work for CHP and other law enforcement agencies statewide.

Police agencies sometimes call in a drug recognition expert when an officer suspects drugged driving but doesn’t have the training himself.

In late November, Sacramento officers responded to a driver who had hit a barrier near Capitol Mall, police said. While officers found “marijuana scattered throughout the vehicle,” they also needed CHP’s help to evaluate the driver, according to a police report. The driver was arrested on suspicion of driving under the influence.

CHP faces challenges training officers on marijuana impairment. The agency cannot provide pot to subjects on which officers practice their evaluations because of the federal prohibition on marijuana, said Sgt. Glen Glaser.

Stoned driving suspects go through the same field tests as drunken driving suspects, such as standing on one leg, he said.

The course includes a three-hour section on cannabis. Officer Travis Herbert of the Woodland CHP office teaches the section and was able to get CHP approval to seek a medical marijuana card. He said he got it at a medical marijuana festival from a gynecologist after saying he needed pot for marital stress. The only reason he got the card was to illustrate how easy it is to obtain one, he said, adding he does not consume marijuana.

In a recent class, Herbert told officers that marijuana slows reaction time, dilates the eyes and creates droopy eyelids. He cautioned that such characteristics can be caused by reasons other than drug impairment, such as a medical condition, and encouraged officers to look at the “totality of the evidence,” starting with erratic driving.

The Legislature recognized the difficulties in enforcing stoned driving when it included $1.8 million to fund research at UCSD. Participants in the study consume marijuana and are monitored as they use driving simulators. Researchers are examining whether iPads could bolster field sobriety tests through cognitive tests. They’re also examining whether a breath or saliva test could effectively measure marijuana impairment.

The research is expected to be complete in two years.

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