The $1.2 trillion infrastructure bill that became law last week earmarks billions for projects to improve safety for cars and trucks and protect properties from floods and wildfires. But one of the provisions most welcomed by insurers doesn’t appropriate any money at all.

After President Joe Biden signed the Infrastructure Investment and Jobs Act on Nov. 15, the American Property and Casualty Insurance Association issued a press release calling attention to Section 25026: report on marijuana research.

That new code section directs the secretary of transportation to submit a report to Congress in two years identifying any barriers preventing research that can lead to developing a method of identifying individuals who are impaired by marijuana. The report must also recommend methods of making available to researchers the many strains of marijuana that are now legally available.

“The inclusion of these provisions is an important, albeit first, step forward in combating cannabis impaired driving,” stated Nat Wienecke, senior vice president of federal government relations for the APCIA.

Christy Thiems, a senior director for the APCIA, said during a telephone interview that her organization has been struggling for years to get policymakers to address the impact of marijuana impairment on highway safety. She said industry research on the topic started almost as soon as Colorado became the first state to legalize recreational use of marijuana in 2012.

Since then, 17 other states and the District of Columbia have legalized recreational use.

In 2019, the Insurance Information Institute published a white paper asserting that early evidence suggests legalization resulted in an increase in traffic accidents. The institute cited Highway Loss Data Institute statistics that showed collision claim frequency was 12.5% higher in Colorado and 9.7% higher in Oregon than nearby states that had not legalized recreational use of marijuana. The HLDI also found a 1% higher claims rate in Oregon, which had also legalized marijuana, but did not consider that statistically significant.

Dale Gieringer, director of the California chapter of the National Organization for Reform of Marijuana Laws, said he is skeptical about linking higher collision claim rates to legal marijuana.

“Numerous other studies have found no change in traffic fatalities under legalization in Canada, Colorado, Washington, and elsewhere, Gieringer said. “In California, DUI arrests have posted record lows in recent years. The Netherlands, where cannabis has been legally available for 45 years, has one of the lowest accident rates among developed nations.”

Gieringer said he is also skeptical that more research will lead to the development of a reliable test to determine if a motorist is impaired by marijuana.

“The consensus is that it’s impossible to determine impairment based on chemical tests of blood, urine, breath, saliva or other bodily fluids,” he said. “In this respect, marijuana differs from alcohol, as do most other legal, impairing drugs such as benzodiazepines, opiates, amphetamines etc, for which no DUI standards have been set. For this reason, NORML strongly advocates performance-based impairment tests like the field sobriety test commonly employed by the Highway Patrol.”

In the white paper, the Insurance Information Institute laments that there is no equivalent to the breathalyzer to check marijuana levels to determine if a driver is impaired.

Five states have established limits on the amount of THC that can be detected in blood, above which it is illegal to drive. Colorado, for example, established a THC limit of 5 nanograms per milliliter. Eleven states have zero tolerance; motorists can be convicted of drug impaired driving if any amount of THC is found in their blood.

California and Oregon, on the other hand, have resisted establishing any maximum level because THC can remain the the bloodstream long after any intoxication subsides.

A federally-funded research paper published in 2020 shows that there is a reason to be skeptical about relying on bodily fluids to determine whether a driver is impaired by marijuana.

Researchers with RTI International, funded by a grant from the National Institute for Justice, found that only six of 165 people who orally ingested 25 mg of THC reached a blood THC level greater than Colorado’s limit of 5 ng/mL. However, those same research participants exhibited substantially decreased performance on cognitive and psychomotor assessments.

The research also showed that standard field sobriety tests were not effective for detecting marijuana intoxication. What’s more, the participants displayed wide differences in the degree of impairment after ingesting the same amount of marijuana.

“Our work indicates that THC is not a reliable marker of cannabis impairment,” the paper concludes.

Thiems said the language in the infrastucture bill is significant because it recognizes that there are no reliable tools to determining a motorist’s degree of impairment. She said many motorists are deterred by the social stigma surrounding driving after consuming alcohol, but that stigma does not exist to the same degree for marijuana use. In fact, she said, studies have shown that marijuana is perceived as less dangerous for motorists than alcohol. She said harmful myths have developed, such as that marijuana improves safety because motorists drive slower.

In fact, marijuana impairs judgment and reaction time, Thiems said. She said establishment of a clear standard that establishes when a motorist is impaired will help enforce drug-impaired driving laws and increase public awareness about the impact of marijuana on safety. The same standard can also be used to inform decisions about workplace safety.

“As more states legalize marijuana, it’s important to fully understand the risks associated with working or driving under its influence,” Wienecke said in the APCIA press release. “Simply put, without more research, no one can say, ‘how high is too high’ to drive or work.”

*This story ran previously in our sister publication Claims Journal.