Lack of Clear Marijuana Consumption Measurement Method Could Make It Hard for State to Prove Driver Impairment

Being a defendant in a DUI case can make you feel like you’re in an unwinnable situation. Fortunately, that is not always true. Some DUI defendants do get caught driving impaired and eventually get convicted. Others get charged with DUI and don’t get convicted for one reason or another. One common reason that a DUI defendant might not get convicted is that the state was unable to produce sufficient proof that the driver was impaired by alcohol or a drug.

When an officer suspects a driver is driving under the influence of alcohol, they have a fairly reliable method for determining whether the driver was impaired at the time that they got pulled over. Blood and breath tests that measure alcohol provide clear answers about whether the amount of alcohol in a defendant’s body was over the legal limit at the time they got stopped. There is still room for error in testing for alcohol, as well as room for mistakes with the traffic stop, the arrest, and other things that lead to DUI charges, so it is crucial that DUI defendants seek assistance from a DUI defense attorney to give themselves the best chance at avoiding conviction.

The legalization of marijuana poses an interesting problem for the law enforcement officers charged with the task of finding and arresting drivers who are impaired by marijuana. Sometimes, the presence of a marijuana smell in a vehicle can persist for hours. Also, a person who responds in the affirmative to having used marijuana recently is often capable of passing the field sobriety tests that officers use to assess driver impairment. There is no marijuana-detection equivalent to the breathalyzer tests that are used to detect alcohol. Additionally, there is no “legal limit” on the amount of marijuana that a person can have in their body that would render them impaired per se. All of these things add up to a situation in which it is much harder to prove driver impairment due to marijuana use than driver impairment from alcohol.

While it is difficult to prove driver impairment from marijuana use, it is not impossible, and police are doing what they can to stop, examine, and arrest marijuana-impaired drivers. For example, there are some experts who are trained to determine impairment. There are also thousands of California Highway Patrol Officers who have gone through the Advanced Roadside Impaired Driving Enforcement program, which teaches them to perform a twelve-step examination of drivers suspected of being impaired by marijuana. As is the case with DUI arrests for alcohol impairment, the twelve-step assessments are not foolproof, so defendants who get examined should not assume that they will get convicted.