With the increased use and legalization of marijuana, law enforcement and legislators are working harder than ever to answer the public’s pressing questions. Some of the areas they are attempting to address include the effects marijuana use can have on driving, how a law enforcement officer can detect the use of marijuana, how levels of marijuana are measured, and the level the drug’s active ingredient needs to be in a driver’s system for him or her to be considered impaired.

Currently, there are no satisfactory or accepted answers to any of these questions. All states across the country have the same approach when it comes to detecting the use of alcohol and determining the level of the driver’s impairment—breathalyzer and blood tests are widely used by law enforcement to determine if a driver is impaired, and a Blood Alcohol Concentration (BAC) of 0.08 percent or more is the national standard for determining if a driver is too impaired to safely operate a vehicle.

Lack of Marijuana, THC Data Makes Detecting Impairment Difficult

These types of standards do not current exist for marijuana use, but many states have taken their own approach to criminalizing the use of marijuana while driving. One of the more popular approaches involves what are known as “per se” laws, which make driving with specific levels of THC, marijuana’s active ingredient, in a driver’s system illegal. Per se laws were recently considered by the state of Oregon, but an Oregon House Bill Legislative Report pointed out some major flaws with this tactic.

According to the report, professionals stated that the manner in which the human body processes marijuana, which is vastly different than how it processes alcohol, makes it difficult to accurately detect the concentration of THC present in the body as well as its intoxicating effects. Additionally, the report stated that it is very difficult for law enforcement officers to accurately detect the recent use of marijuana while working in the field.

The Oregon House Bill Legislative Report that was released after per se laws were suggested also stated that the lack of data regarding THC and marijuana, as well as the restrictions placed on researching these substances, makes it difficult to make accurate statements about the effects THC has on an individual’s ability to drive. With this evidence, it is clear to see that the use of per se laws may not be the best approach to handling marijuana use while driving.