Despite the trend toward legalization of marijuana in the states, the substance remains classified as an illegal drug under U.S. federal law. In fact, federal law places marijuana in the most dangerous drug category along with heroin and LSD.

That means that if you’re on a boat in federally patrolled waters, you could be convicted of a serious crime if you smoke pot or have it in your possession. The U.S. Coast Guard enforces federal law, which overrides state laws. Federal law does not even recognize an exception to allow for medical marijuana use.

U.S. Laws Can Apply Virtually Everywhere at Sea

If you are in international waters on a boat registered in the U.S., maritime laws specify that you are still subject to the restrictions of U.S. federal law. Moreover, the U.S. Coast Guard can board commercial and recreational vessels to check for safety equipment even when those vessels are in state-controlled waters. If they find marijuana or believe someone was operating a boat while under the influence, violators could face substantial penalties.

A Warning for Mariners

The federal restrictions pose a particular concern for those who work on the water. Mariners who test positive for marijuana face serious consequences such as: 

• Termination from employment
• Loss merchant mariner credentials
• Loss of the ability to perform certain duties deemed safety sensitive

Tests for marijuana use can detect both inactive THC in urine and active THC in the blood for a considerable time after smoking or ingesting the substance. Even when someone uses a CBD product that does not contain THC, the product may contain sufficient quantities of psychoactive THC to trigger a positive result in a drug test. The bottom line is that to avoid putting their jobs at risk, mariners should not use marijuana, CBD oils, or any cannabis products.