Can You Be Arrested for Driving Under the Influence of Marijuana in New Mexico?
Short answer? Yes. Even though marijuana is legal for adults in New Mexico, driving while impaired by it is still against the law—and officers have the authority to arrest you if they believe you’re under the influence.
Let’s break down how this works and what you need to know if you’ve been charged with a marijuana-related DWI.
Marijuana Is Legal—But Impairment Still Matters
Just like alcohol, marijuana is legal for adults to use recreationally. But also like alcohol, it becomes a crime when it affects your ability to drive safely.
Under New Mexico law, driving while even slightly impaired by any drug—whether it’s marijuana, a prescription medication, or something illegal—is considered Driving Under the Influence (DUI).
And it doesn’t take much. If an officer sees signs that your mental or physical ability to drive is affected in any way, that can be enough to justify an arrest.
There’s No “Legal Limit” Like Alcohol
Unlike alcohol (where .08 BAC is the legal threshold), marijuana has no clear-cut number that proves or disproves impairment.
Yes, there are reference points in New Mexico statute (such as 50 ng/mL for THC metabolites), but these aren’t hard legal limits. Even a small amount of THC in your blood can trigger suspicion—and it can stay in your system for days or weeks after use, long after the impairment has worn off.
What really matters is how you appear and behave behind the wheel.
So How Can Officers Tell if I’m High?
Police in New Mexico look for certain behaviors and indicators that suggest marijuana impairment. These may include:
Bloodshot or watery eyes
Slurred speech
Slowed reaction times
Difficulty following directions
Unsteady balance
The smell of marijuana in the car
Visible marijuana or paraphernalia
Driving errors (weaving, crossing lanes, delayed starts)
If these signs are present, officers may arrest you for DWI—even without a breathalyzer result.
What About Drug Tests?
There are blood and urine tests that detect marijuana use. However:
THC can remain in your blood for 12–24 hours, even longer for regular users
Some tests detect only metabolites, which don’t indicate recent use or impairment
No test currently measures real-time impairment the way alcohol breath tests do
Because of this, officer observations often carry more weight than a drug test in marijuana DWI cases.
What’s the Penalty for a Marijuana DWI?
The penalties for marijuana-related DWIs in New Mexico are the same as alcohol-based DWIs:
First offense: Up to 90 days in jail, a fine up to $500, license revocation, and mandatory ignition interlock
Subsequent offenses: Harsher penalties, including longer license revocations, possible felony charges, and mandatory jail time
You could also be required to complete community service, attend drug education classes, or install an ignition interlock device.
Can Officers Just Assume I’m High?
Officers can’t arrest you just because marijuana is present in your system. But if your driving behavior is unsafe and you show signs of impairment, they have probable cause to act—even if it’s based on observations rather than a precise THC level.
Some officers are trained as Drug Recognition Experts (DREs) who use a multi-step process to evaluate whether someone is impaired by drugs. Their testimony can be powerful in court—even without chemical evidence.
What Should You Do If You’re Arrested?
If you’ve been charged with driving under the influence of marijuana, your case is defensible—but you need legal help fast.
At the Victor Titus Law Firm in Farmington, we understand how frustrating it is to face DWI charges when you weren’t drunk—and maybe weren’t even impaired. We’ll review the officer’s report, challenge weak evidence, and fight to protect your license and your record.
Call (505) 326-6503 today for a free consultation. Don’t let unclear laws and outdated science determine your future.