Editor’s note: Reporter Elizabeth Hewitt spent a week in Colorado earlier this month to look at lessons learned in the state that first opened recreational marijuana sales. Vermont lawmakers are expected to consider similar legislation in January.
COLORADO SPRINGS — As more states loosen restrictions on marijuana by opening up medical and recreational sales, the question of how to enforce safety on the roads looms large across the country.
Marijuana presents a particular challenge. Unlike with alcohol, there is no clear chemical test that can be administered roadside to determine whether a driver is impaired by pot.
In Colorado, where legal marijuana sales began in January 2014, the state addressed the potential for increased impaired driving by expanding the ranks of law enforcement officers trained to recognize drug impairment.
Now, three years into legalization, statistics show some increase in marijuana-impaired drivers. However, challenges with data collection make it difficult to know just how legalization has affected safety on the roads.
“I think it hasn’t been enough time to go by to really get a clear-cut picture,” said Cmdr. Sean Mandel of the Colorado Springs Police Department.
Mandel pointed to practical challenges in collecting data on whether impaired driving has increased since Amendment 64, the constitutional measure that legalized pot in Colorado, took effect.
One issue, he said, is that law enforcement does not always test impaired drivers for marijuana. That requires obtaining a warrant to have a blood sample taken at a facility such as a hospital.
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When an officer in Colorado Springs encounters a driver who appears to be under the influence of a substance, the officer might not go to the trouble of testing for pot if the person shows clear signs of being above the legal limit for alcohol.
“Ninety-nine out of 100 times, they’ll process them for the alcohol instead of the marijuana because it’s just simpler,” Mandel said.
Data from 2013 and 2014 indicate that fatalities in collisions involving a driver who tested positive for tetrahydrocannabinol, or THC — an active chemical in marijuana — increased after legalization, according to a report on marijuana legalization from the Colorado Department of Public Safety published in March.
In 2013, 55 fatalities occurred in crashes where a driver had THC in his or her system — just over 11 percent of all fatalities on Colorado roads that year. The following year, after legalization took effect, there were 79 deaths on the roads where a driver’s system contained THC, or 16 percent of all fatalities.
The report also looks at the data in a different way: the proportion of drivers in fatal crashes who were found to have THC in their system. That number also increased slightly. The report does not indicate whether THC was detected in the driver at fault or in one not at fault, nor does it indicate that the driver was impaired at the time.
The report notes some issues with the data. For one thing, not all drivers in crashes are tested for substances. In 2014, 81 percent of drivers who died in a crash were tested for substances, but just 14 percent of those who survived. Also, because of recent changes to how fatalities are reported, the report does not include data from before 2013.
Statistics on arrests for driving under the influence also provide fodder for considering how legalization affected safety on the roads. However, as noted in the report, the data have some shortcomings. There is no criminal charge specific to driving under the influence of drugs rather than alcohol, though there is an attempt to record substances involved in an arrest for the purpose of data collection. The state does not have a centralized system for tracking toxicology test results, nor does it track across all state, county and local law enforcement agencies.
An additional issue could be under-reporting, as Mandel described. Police processing someone for DUI might not test for drugs if a charge based on alcohol use is an option.
Colorado does have a legal threshold for marijuana impairment: five nanograms of delta 9-THC, (the psychoactive element in marijuana) per milliliter of blood. An officer who has probable cause to believe a driver is under the influence of pot can detain the person to initiate the blood testing process. However, marijuana impairment functions differently than alcohol impairment and THC levels do not necessarily indicate that someone is high.
The Colorado State Patrol is responsible for a fifth of all arrests for driving under the influence, according to the report.
State patrol data, which the agency began collecting in 2014, show that total DUIs dropped 18 percent from 2014 to 2015, driven largely by a decrease in the number of citations for alcohol-only DUI.
Marijuana-only DUI citations decreased from 354 in 2014 to 347 in 2015. Multi-substance citations involving marijuana remained fairly steady.
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The report also looked at enrollments in a treatment class mandatory for all drivers convicted of DUI in Colorado to see how marijuana-impaired driving rates have changed.
The state saw a decrease in all DUI admissions to the class of 12 percent between 2007 and 2014. However, during that time, the number of people admitted to the class primarily for marijuana impairment increased 48 percent.
Trooper Josh Lewis, of the Colorado State Patrol, said drug-impaired driving predates marijuana legalization.
“Troopers in the Colorado State Patrol have been dealing with impaired drivers since we were created in 1935. Marijuana and drugged drivers are not anything new,” Lewis said. “What is new are changes in technology and training.”
The state used tax dollars raised from the marijuana industry to pay for three types of drug impairment recognition training in fiscal year 2015, according to the Colorado Department of Public Safety report.
Every trooper in the State Patrol either already has or will go through training under the Advanced Roadside Impaired Driving Enforcement program, according to Lewis.
More than 50 officers on the force are now certified drug recognition experts — a higher level of training than ARIDE.
The state also provided a “Marijuana 101” class for law enforcement officers.
With legalization, the state launched a push to increase the number of law enforcement officers credentialed to recognize drug-impaired driving. Colorado increased the total number of drug recognition experts across all law enforcement agencies from 129 officers in 2012 to 228 in November 2015.
Lewis said the trainings help troopers identify signs of impairment from drugs or from multiple substances.
All drivers suspected of impaired driving are handled the same, Lewis said. Officers use roadside maneuvers, face-to-face interaction, and general observation to determine if a person can safely drive. If they suspect a driver is high on pot, they may seek a blood test.
“There is no one, single ‘red-handed’ clue that any officer uses,” Lewis said. “It is the sum of the parts overall.”
If new technology to detect impairment from drugs is developed and improved, he said, the patrol may use it — but it will still be just one tool available to officers, he said.
“As new and improving technology continues to develop, we will explore what are the best options for both troopers to use and to keep the roadways of Colorado safest,” Lewis said.
In Denver, the state’s largest city, the number of impaired driving incidents involving marijuana doubled the year legalization took effect, according to the city’s annual report.
DUI citations involving marijuana, either alone or in combination with other substances, increased from 33 in 2013 to 66 in 2014 and 73 in 2015. However, the report notes that despite the increase, marijuana-related DUIs are just 2.8 percent of all impaired driving arrests in the city.
“Impaired driving is a concern, but people have been driving stoned for a long time,” said Dan Rowland, the city of Denver’s communication adviser. “People are also out there driving drunk and under the influence of prescription medication.”
Rowland said impaired driving is just one of many concerns for law enforcement since legalization took effect. He pointed to other issues, including activity related to the illicit market in marijuana.
“The black market outside of Colorado continues to flourish, and there is high demand for Colorado-grown product,” he said. “From a public safety standpoint, we continue to see issues with diversion and illegal cultivation outside of our regulated market.”
Clarification: This story was edited at 12:18 p.m. Dec. 30 to clarify that THC levels do not necessarily indicate that someone is high. Also, data of THC involvement in fatal accidents do not indicate whether THC was found in the driver at fault or one not at fault, nor tells if the driver was impaired at the time.
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