Can You Drive With a Medical Marijuana Card in Pennsylvania?

Many people assume that if they have a Pennsylvania medical marijuana card, they are legally protected when driving.

Unfortunately, that is not the case.

While medical marijuana is legal in Pennsylvania, driving under the influence of marijuana can still lead to a DUI charge, even if the marijuana was legally prescribed.

Understanding the law is important for anyone who participates in Pennsylvania's medical marijuana program.

Medical Marijuana Is Legal in Pennsylvania

Pennsylvania legalized medical marijuana under the Pennsylvania Medical Marijuana Act (Act 16).

Patients with qualifying medical conditions may legally obtain marijuana products from licensed dispensaries if they have a valid medical marijuana card.

However, the law specifically provides that patients may not operate a motor vehicle while under the influence of marijuana.

So while possession and use may be legal, impaired driving is still illegal.

Pennsylvania's Marijuana DUI Law

Pennsylvania's DUI statute, 75 Pa.C.S. § 3802(d), creates two ways someone can be charged with a drug-related DUI.

A driver may be convicted if:

1. The driver is impaired by a drug, or
2. The driver has any amount of a Schedule I controlled substance in their blood.

This second provision is what often surprises medical marijuana patients.

Unlike alcohol DUI cases, which require proof of a 0.08% blood alcohol level, Pennsylvania law historically allowed a DUI conviction if any amount of marijuana (THC) is present in the bloodstream.

That means a person could be charged even if they were not visibly impaired.

THC Can Remain in Your System Long After Use

Another complication is that THC can remain detectable in the bloodstream long after the impairing effects wear off.

Depending on the person, THC may remain in the blood for:

• Several hours

• A full day

• Sometimes longer in regular users

This creates a situation where a person could feel completely sober but still test positive on a blood test.

For medical marijuana patients who use cannabis regularly for treatment, this creates a significant legal risk when driving.

Possible Changes to Federal Marijuana Law

There has been growing discussion about changing marijuana's classification under federal law.

In late 2025, President Donald Trump issued an executive order directing federal agencies to expedite the process of rescheduling marijuana from Schedule I to Schedule III under the federal Controlled Substances Act.

Schedule I drugs are considered to have no accepted medical use, while Schedule III drugs have recognized medical uses and a lower potential for abuse.

However, it is important to understand that this executive order did not immediately change the law.

Under federal law, the Drug Enforcement Administration (DEA) must complete a formal rule-making process before any change to the drug schedule becomes effective. Until that process is completed, marijuana technically remains classified as a Schedule I controlled substance under federal law.

Would Rescheduling Change Pennsylvania DUI Law?

Even if marijuana is eventually moved to Schedule III federally, Pennsylvania DUI law would not automatically change.

Pennsylvania's DUI statute currently references Schedule I substances and also separately criminalizes driving while impaired by any drug.

If marijuana were removed from Schedule I, the “any amount” DUI provision could become legally questionable when applied to marijuana cases.

Some legal experts believe this could eventually require changes to Pennsylvania law or new court decisions clarifying how DUI marijuana cases are prosecuted.

However, as of now, Pennsylvania courts still enforce the current DUI statute, and marijuana-related DUI charges remain common.

Having a Medical Marijuana Card Is Not a DUI Defense

Many patients assume their medical marijuana card protects them from DUI charges.

It does not.

Even lawful medical marijuana patients may still be charged with DUI if:

• Police believe they are impaired, or

• A blood test detects THC in their system.

Possible Defenses in Marijuana DUI Cases

Every case is different, but there may still be defenses available depending on the circumstances.

Possible defenses may involve:

• Challenging whether the driver was actually impaired

• Questioning the legality of the traffic stop

• Challenging the blood testing procedures

• Issues with the handling or chain of custody of the blood sample

Because marijuana DUI cases often rely heavily on blood test evidence, they frequently involve technical legal and scientific issues.

Charged With a Marijuana DUI in Pennsylvania?

If you have been charged with DUI involving marijuana, it is important to speak with an attorney who understands the complex interaction between medical marijuana laws and Pennsylvania DUI statutes.

These cases require careful analysis of police procedures, blood testing, and evolving marijuana laws.

Paul M. Aaroe, Esq. — “The DUI Guy™”

Aaroe Law Offices, P.C.

Easton, Pennsylvania

📞 610-559-8680

🌐 www.aaroelaw.com

If you or a loved one has been charged with DUI in Pennsylvania, contact Aaroe Law Offices for a confidential consultation.