Marijuana DUI – Debate Over Legal Limits

Marijuana DUI Debate Is Picking Up Steam

Now that several states have made it legal to purchase and use marijuana, either recreationally or for medicinal purposes, it is not surprising that new challenges and questions surrounding the use of the drug are arising. In fact, these states are beginning to wrestle with the question of how to assess impairment of drivers who have used the drug. This task is not proving to be simple. For several reasons, determining when a driver is impaired by marijuana use is a much more complicated process than determining impairment due to alcohol.

The Facts About THC

THC, which stands for tetrahydrocannabinol, is the primary “drug” in marijuana. When someone smokes or ingests marijuana, THC is the substance that produces the “high” and potentially causes impairment while driving. 

It might seem that determining if someone is high from marijuana use would be simple, but that is not the case. Because marijuana has only recently become legal in some states, levels of THC in various plants are just now coming under regulation. Some marijuana contains higher levels of THC and is potentially more intoxicating than other types. Therefore, the type of marijuana smoked or ingested could have an impact on the level of impairment and could vary from one person to another.

This is not the biggest problem with determining THC impairment, however. THC produces substances known as metabolites that stay in the body and may be detected in the bloodstream up to several weeks after marijuana use. This means that, unlike alcohol, users may show evidence of marijuana smoking or ingestion long after the effects of the drug have worn off.

Per Se and Legal Limits for Marijuana Use While Driving

In many states, the law requires zero tolerance for any form of marijuana use. In states in which marijuana is illegal, any use, no matter how small, is grounds for an arrest for marijuana dui. However, with the recent legalization of marijuana, law enforcement officials in some places can no longer assume that simply using the drug constitutes a crime. Several states, including Washington, Colorado, Montana, Pennsylvania, Ohio and Nevada, have now passed laws that set a legal limit for a per se charge of impairment for those driving with detectable levels of marijuana metabolites in their bloodstreams.

Officer determines impairment of marijuana dui suspectA per se charge is one that allows law enforcement officials to arrest the driver for impairment simply based on a measured level of drug use. This is simple enough when it comes to alcohol impairment; every state in the nation now recognizes .08 percent blood alcohol content as the per se limit. Once a driver’s blood alcohol content reaches this level, the state can automatically charge the driver with DUI without having to show additional evidence of impairment.

However, a per se charge may not always be as logical for those who are arrested for driving while under the influence of marijuana. Currently, the most reliable test for marijuana use is a blood test. However, even if a blood test shows a per se legal limit of marijuana metabolites, it is by no means certain that the driver was impaired.

Because per se laws can lead to false “positive” arrests for DUI when it comes to marijuana, many states are being urged to reject these laws in favor of those that allow law enforcement to make a determination of impairment at the scene when a driver is pulled over. Proponents of the “effect-based” approach argue that this is the only fair way to determine if a driver is actually suffering from the effects of marijuana or if the metabolites in his or her blood are left over from previous use. Detractors argue that a lack of standardization of the term “impaired” would make this approach far too subjective and open to abuse on the part of police officers.

How To Fix The Marijuana Impairment Problem

The problem of marijuana per se impairment has now come to the attention of the public. Through a series of court cases, those who have been arrested for marijuana DUI are challenging the per se marijuana impairment laws, claiming that they are unfair.

The American Automobile Association or AAA, a group which is highly influential in passage of insurance and driving laws, stated recently that blood tests for marijuana impairment are poor indicators of the actual risk associated with the driver and that these tests have questionable scientific validity. In addition, AAA was quick to point out that the use of any drug before driving is unsafe. The group urged caution when driving after using marijuana, pointing to a study of Washington State that showed that after marijuana was legalized, fatal accidents involving drivers who had used the drug had doubled. More information from AAA on the subject of impaired driving and Marijuana.

The AAA study raises an interesting question: is marijuana use to blame for the increase in fatal accidents, or is legalization actually the driving force? Some experts feel that the reason there has been an uptick in marijuana-related driving accidents is because users are now less likely to fear arrest and are more likely, therefore, to use marijuana before getting behind the wheel. The AAA supports effect-based laws that allow police officers to make a judgment of impairment based on the driver’s behavior as the way to curb dangerous driving and to deter others from using marijuana before getting behind the wheel. 

Whatever the solution, it is clear that the passage of laws to legalize the use of marijuana must be followed up with laws to punish those who drive while impaired. The question remains how to successfully identify those who are actually impaired and punish them fairly to keep the highways safe from dangerous drivers.