With Pot Shops Opening Soon, Massachusetts Warns of Dangers of Driving High

In anticipation of the first recreational marijuana stores opening within Massachusetts in the coming weeks, state officials Wednesday stepped up warnings to motorists about the risks of driving while stoned.

A new public education and enforcement campaign announced by Republican Gov. Charlie Baker’s administration – which also renews warnings against alcohol-impaired driving – implores marijuana users to consider alternatives to getting behind the wheel, such as public transit, designated drivers or ride-hailing services such as Uber and Lyft.

“It’s not uncommon to hear people say, ‘I drive better when I’m high,”’ said Jennifer Queally, the state’s undersecretary for public safety. “It wasn’t true about alcohol … and it is absolutely false for marijuana and other drugs. People do not drive better when they are high.”

Massachusetts officials said they were not prepared to recommend a legal threshold for pot in the blood system, as some legal marijuana states have done.

Colorado and Washington, for example, established limits of 5 nanograms per millimeter of THC – the psychotropic chemical in cannabis – above which a driver could be consider impaired.

Such limits have been criticized as arbitrary because – unlike alcohol – there is as yet no universally accepted scientific measurement for marijuana impairment. Traces of THC can also remain in a person’s blood system for days or even weeks, making it more difficult to accurately assess whether a motorist is high.

A special commission created to examine issues around drugged driving was scheduled to hold its next meeting Friday and make recommendations to the Legislature by Jan. 1.

Police often rely on their own observations during traffic stops to determine if a driver’s ability to operate a motor vehicle is compromised by marijuana, said State Police Maj. Richard Ball.

“Your muscle control, your physical motor skills, your perception, your anxiety levels, your heart rate, your pulse – under narcotics all these change,” he said.

According to the U.S. Centers for Disease Control and Prevention, marijuana can distort perception and slow a driver’s reaction time and decision-making ability.

Data showed marijuana to be the drug most frequently found in drivers involved in fatal crashes in Massachusetts between 2012 and 2016, officials said, also citing studies that pointed to increased marijuana-related traffic fatalities in states that previously legalized recreational cannabis.

“Massachusetts cannot follow this trend,” said Queally.

The first pot shops in the eastern United States had originally been expected to open around July 1 in Massachusetts.

The state’s Cannabis Control Commission has granted provisional licenses to medical marijuana dispensaries in Leicester, Northampton and Brookline to begin selling recreational pot, and regulators planned to vote Thursday on three additional retail licenses for stores in Plymouth, Wareham and Easthampton.

None of those stores can open, however, until the agency licenses a facility to test cannabis products for THC concentration and possible contaminants.

Commissioner Jennifer Flanagan said Wednesday she could offer no timetable for when an application for a testing lab might come before the panel for approval.