Is Marijuana DUI Treated the Same as Alcohol DUI in Virginia?

 Posted on December 21, 2025 in Drug DUI

In Virginia, marijuana DUI and alcohol DUI fall under the same driving under the influence law, but they are handled very differently in practice. That difference matters because it affects what evidence police rely on and how these cases are defended.

Our Reston, VA DUI defense lawyers come across a great deal of confusion around this issue, especially as marijuana laws have changed in recent years. As of 2025, Virginia law still makes it illegal to drive while impaired by marijuana, even though possession laws are no longer the same as they once were.

What Virginia Law Says About DUI Charges

Virginia DUI charges are governed by Virginia Code § 18.2-266. This law prohibits driving while impaired by alcohol, drugs, or a combination of both. That includes marijuana. Although alcohol and marijuana are covered by the same statute, the way impairment is proven is not the same. Alcohol cases rely heavily on numerical testing. Marijuana cases do not.

How Is Alcohol DUI Typically Proven in Virginia?

Police typically use breath tests and, in some cases, blood tests to measure blood alcohol concentration. A blood alcohol concentration of 0.08 or higher allows prosecutors to argue impairment based on the test result alone. This makes alcohol DUI cases more straightforward from an evidence standpoint.

How Is Marijuana DUI Proven Differently in Virginia?

Marijuana DUI cases do not have a per se limit in Virginia. That means there is no specific THC level that automatically proves impairment. Because of this, prosecutors must rely on a broader range of evidence. Officers often point to the following:

• Driving behavior observed before the traffic stop

• Statements made during the stop or investigation

• Performance on field sobriety tests

• Physical observations, such as coordination or alertness

• Blood test results showing the presence of THC

Keep in mind that THC can remain in the body long after its impairing effects have passed. This makes it harder to prove impairment because a positive test alone does not show whether the driver was actually impaired at the time of driving.

Do Field Sobriety Tests Work the Same Way in Drug and Alcohol DUIs?

Field sobriety tests are used in both alcohol and marijuana DUI cases, but they were originally designed to detect alcohol impairment. Their accuracy becomes less clear when marijuana is involved.

Medical conditions, fatigue, anxiety, or uneven road surfaces can affect test performance. Poor results do not automatically establish marijuana impairment, which is why these tests are often closely examined in court.

What Is Implied Consent in Virginia Marijuana DUI Cases?

Virginia’s implied consent law, Virginia Code § 18.2-268.2, applies to both alcohol and marijuana DUI arrests. After a lawful arrest, drivers are required to submit to chemical testing.

Because breath tests cannot detect THC, marijuana DUI cases usually involve a blood test instead. Keep in mind that refusing that test can trigger a separate license suspension. That suspension can remain, even if the DUI charge itself does not end in a conviction.

How To Fight a Marijuana DUI Case in Virginia

Marijuana DUI cases often focus on whether the evidence truly shows impairment at the time of driving. Possible defense approaches may include:

• Questioning whether the traffic stop was lawful

• Challenging field sobriety tests designed for alcohol, not marijuana

• Arguing that THC presence does not prove current impairment

• Reviewing whether blood testing procedures were followed correctly

• Identifying inconsistencies in officer observations or reports

Schedule a Free Consultation With Our Vienna, VA DUI Defense Attorney

At Arrested for a DUI, LLC, we help clients navigate these complex cases with a clear, informed approach. Our legal team brings more than 30 years of combined experience and is deeply engaged in the Hispanic community, frequently commenting on and responding to local and national issues affecting Latin Americans and immigrants.

Call 301-479-5466 to speak with our Reston, VA DUI defense lawyers about your situation and schedule your free consultation. Se habla Español.