Six states where marijuana use is legal whether for medical or recreational purposes have set specific limits for THC, the high-inducing chemical in the cannabis plant, in the driver’s blood to determine impairment.
A recent study by the AAA Foundation for Traffic Safety concluded that it’s not possible to set a threshold, or to judge based on the legal test that’s apparently without reliable scientific basis.
Thus, the nation’s biggest automobile club recommends scrapping DUI of marijuana laws in Colorado, Pennsylvania, Montana, Nevada, Ohio, and Washington.
Guilty or Not Guilty?
The study they have commissioned said it’s not possible to set a blood-test limit for THC that can reliably determine cannabis impairment, yet the laws in 5 out of 6 states implement the legal tests.
They would necessarily deduce a driver is guilty if the test results show higher THC than the threshold, and not liable if a driver test lower- free to go back behind the wheel.
There is no science that drivers become impaired upon reaching a particular level of cannabis THC in their blood, rather greatly depends on the individual.
Moreover, the tests as inefficient for it requires getting a warrant prior to taking a driver to a hospital for a blood sample to check for the cannabis chemical, which typically takes about two hours.
Drivers who are regular cannabis users with relatively high levels of the chemical might not be deemed impaired.
Some users tend to be far more affected by a small amount compared to others, so those with low THC blood levels could still be a serious risk though they aren’t frequent users.
There are drivers who are impaired by cannabis at the time they are stopped by the police, but since active THC rapidly dissipates, it would have fallen below the threshold by the time the tests are conducted.
In addition to that, the fact that cannabis lingers in the system for up to a month makes it impossible to know if the driver smoked marijuana mere hours ago or a couple of weeks ago.
Testing for THC VS Testing for alcohol
AAA’s president and CEO, Marshall Doney, says that both lawmakers and the public share the strong desire of creating legal limits for marijuana impairment.
However, the cannabis test approach which follows the same manner blood alcohol levels are determined is flawed for they are simply not the same.
The study notes that determining actual impairment due to cannabis THC consumption is quite different from the consumption of alcohol whereas an alcohol level of above 0.08 in the blood is considered legally impaired.
The foundation suggests replacing the laws with a more reliable process, such as letting specially-trained law enforcement officers screen for cannabis use indicators and thereby make their own judgment if a driver is impaired or not.
They would consider various signs of drug use including pupil dilation, the color of the driver’s tongue color, and his or her behavior.
It would still be backed up by a test based on the presence of THC in cannabis instead of a specific threshold.
Safety on the Road
New York University professor Mark A. R. Kleiman, a specialist in drug issues and criminal policy, said the cannabis laws make no sense.
It’s not a law one can obey except by never smoking or using cannabis, or never driving at all, and suggests that states should just consider making it a traffic violation.
Driving under cannabis influence poses the same risk as a noisy child in the back of the car, which doubles the possibility of a crash.
Talking on a hands-free cellphone quadruples crash risks, while a high level of blood alcohol content increases it by about 15 times.
Saving lives through traffic safety, research along with education is AAA’a goal, and their findings on THC blood impairment testing is the perfect place to start clearing out ineffective laws that senselessly send people to jail.
At least three states or as many as eleven will be voting this fall on ballot measures to legalize cannabis whether for recreational use or medicinal purposes or both, while several legislatures may be working on marijuana legalization bills.