Collins & Collins, P.C.

Driving While Stoned - What Is the Standard for Driving and Marijuana?

With the recent marijuana law changes and many more initiatives to come, there are those that fear for public safety with a rash of stoned drivers hitting the roads. The question is whether this is really an issue. After all, there are hundreds of thousands of marijuana users around the country that presumably own vehicles. How has this been addressed in the past? The DWI/DUI statutes in New Mexico clearly cover driving under the influence of marijuana. The question is not whether there are laws to address the issue of driving under the influence of marijuana but how these laws will be enforced.


Albuquerque, NM -- (SBWIRE) -- 12/19/2012 -- The recent marijuana legislation in Colorado and Washington has put a spotlight on smoking and driving. One issue that is getting a lot of attention is how to police the issues of driving while under the influence of marijuana. More to the point, the question is how to protect the public from a real or imagined onslaught of marijuana impaired drivers.

This discussion is not limited to Colorado and Washington. The same issues arise in New Mexico and presumably other states as well since there are no doubt large numbers of individuals that smoke marijuana even in states where it remains illegal to do so. Thus, the issues are worth discussing even for those outside these two states.

In New Mexico, the law has clearly addressed this issue. In fact, the New Mexico laws address driving under the influence of alcohol or drugs. In addition, the law applies to both legal and illegal drugs. The scope of the statutes include even the legal use of prescription drugs. They most certainly include marijuana even if it were legal in New Mexico, which it is not.

The relevant New Mexico statute reads in relevant part as follows: “It is unlawful for a person who is under the influence of any drug to a degree that renders the person incapable of safely driving a vehicle to drive a vehicle within this state.”

The question is not whether or not driving while under the influence of marijuana is illegal in New Mexico; the question is how impairment is to be measured? The New Mexico jury instructions state that to find a person guilty of driving while under the influence of drugs (including marijuana), it must be shown that the driver was “under the influence of drugs to such a degree that the defendant was incapable of safely driving a vehicle.”

Much like the ”impaired to the slightest degree” standard in New Mexico DWI cases, the standard for driving under the influence of drugs is anything but clear. After all, how is it to be determined that the driver was “incapable of safely driving”? Assuming this is done, how might it be shown that this was the result of marijuana?

This standard is no less clear and therefore no less subjective than “impaired to the slightest degree” in New Mexico DWI cases. It is perhaps has even greater potential for abuse due to the special challenges presented by marijuana not present with alcohol or even other drugs. These challenges are related to the length of time that THC will remain in someone’s system after smoking marijuana. Perhaps, the driver has residuals of marijuana in his blood, but it was unrelated to his poor driving. Maybe, he is just a bad driver?

With alcohol, the absorption and elimination rate of alcohol is somewhat well established. There are many arguments to be made on the accuracy of breath alcohol testing under various circumstances. There are even arguments for attacking the testing devices themselves. For the most part, these arguments are made at the margins in close cases. In cases of high breath alcohol levels, the arguments are not as readily available to attack the validity of the testing instruments though testing procedures may still create possible defenses.

In the case of breath alcohol testing, there is well established New Mexico case-law dealing with these arguments. The case-law for marijuana is much less developed. In addition, the standard for impairment has not been firmly established. With alcohol, a driver is presumed intoxicated if his or her breath alcohol level is .08 or above. Of course, the “impaired to the slightest degree” standard can seemingly render this standard meaningless with drivers regularly arrested in New Mexico at well below the .08 level.

With marijuana, there is no presumptive standard of impairment. There is simply the “incapable of safely driving a vehicle” due to marijuana use. The problem is exaggerated further by the distinction between active and inactive THC. Only active THC will impair a driver’s ability to drive. Inactive THC does not.

This will raise issues as to procedures and testing devices for the accurate measurement of active THC. In many cases, the outcome will come down to expert testimony on both sides. The experts will be called upon to address active THC and inactive THC levels in the driver’s blood. The cases will basically become battles of the experts.

So what’s the problem? The problem is that experts are extremely expensive. In fact, the expert could well costs more (significantly more) than the criminal defense attorney. Most people cannot afford an expert for their defense. Consequently, they may have no viable defense at all even in highly suspect cases. Thus, the problem is very real and potentially disastrous for innocent drivers.

So the question that should be asked is not as much how State’s will protect the public from marijuana impaired drivers but how will the State (including New Mexico) protect drivers from unjustified police and prosecution of marijuana smokers.

Will the states create just, balanced and objectively measurable standards for determining marijuana impairment? Or will drivers be left to the whims of officers and prosecutors who may lead some to argue much like impaired to the slightest degree that they know it when they see it? A good expert will shoot those arguments down. The problem is that very few people can afford a good expert!