Oklahoma bill targets marijuana-related DUI testing rules after aggravated DUI changes removed two-hour limit

A proposal aimed at narrowing how marijuana test results can be used in certain DUI cases

An Oklahoma lawmaker has introduced legislation to revise how the state’s driving-under-the-influence statute applies to marijuana, as lawmakers continue to adjust enforcement tools and penalties created during the 2025 session.

House Bill 3018, filed for the 2026 regular session, would change Oklahoma’s DUI statute by carving out an exception for marijuana, marijuana derivatives and synthetic cannabinoids in the law’s “per se” drug provision. Under that provision, it is unlawful to drive with “any amount” of a Schedule I controlled substance—or its metabolites—in a person’s bodily fluids at the time of testing. HB 3018 would keep the Schedule I language in place but add an explicit exception for marijuana-related substances.

Why the bill was filed now

The filing follows legislative changes adopted in 2025 that created an “aggravated DUI” classification. As described in the House author’s announcement, the 2025 amendment also removed a long-standing two-hour window tied to blood testing for Schedule I substances in aggravated DUI cases. The change raised questions for licensed medical marijuana patients because THC can remain detectable in the bloodstream well after the intoxicating effects have passed.

Oklahoma does not set a numerical blood-content threshold for marijuana impairment. That distinction matters because a positive test for THC or related compounds may reflect prior use rather than driving while impaired. Supporters of HB 3018 describe the measure as an effort to avoid DUI liability based solely on lingering test results, while maintaining enforcement options that focus on observable impairment.

What HB 3018 changes—and what it does not

• HB 3018 would amend Title 47, Section 11-902 to exclude marijuana, marijuana derivatives and synthetic cannabinoids from the statute’s “any amount of a Schedule I substance or its metabolites” testing-based prohibition.

• The bill would not eliminate DUI enforcement for marijuana impairment. Oklahoma law separately prohibits driving while “under the influence” of an intoxicating substance other than alcohol when it renders a person incapable of safely operating a vehicle.

• Field sobriety testing and other investigative steps used to assess real-time impairment would remain available to law enforcement, as emphasized in the bill author’s public description of the proposal.

HB 3018 is framed as a targeted adjustment: narrowing the circumstances where a marijuana-related test result alone could trigger liability under a strict “per se” approach, while leaving impairment-based DUI provisions intact.

Legislative status and next steps

The Oklahoma House filed HB 3018 on Jan. 12, 2026. The measure received its first reading on Feb. 2, 2026. As of publication, no committee amendments, floor amendments, votes, or fiscal impact statements were listed on the Legislature’s bill tracking system.

If the bill advances, it will likely sharpen an ongoing policy debate: how to balance roadway safety enforcement with the reality that marijuana test results can persist beyond intoxication, particularly in a state with a large population of licensed medical marijuana patients.