Industry:HR Compliance Added By:Admin Posted On:Aug. 5, 2019
As marijuana laws in the US change, many employers have written their own rules on employee marijuana use. California, home to Silicon Valley, has seen a major shift in how employers approach workers who use it. Medical research describes two kinds of use: as a medicine to treat a condition, and as an illicit or recreational drug. This article explains how legal marijuana consumption at work is and the main legal issues employers face.
States first legalized marijuana for medical purposes, and in recent years many more legal changes have taken effect. Each state treats marijuana differently. Many state laws no longer treat medical or recreational use as illegal, which shapes how employers write their workforce policies.
Even where marijuana is legal, employees are generally prohibited from using it or being under its influence while working.
For decades, federal law classified marijuana as a Schedule I drug, which made it illegal to use even for medical purposes. Schedule I drugs are considered to have a high potential for abuse and can cause impairment. The level of impairment from marijuana depends on its THC (delta-9-tetrahydrocannabinol) content.
That classification has started to change. In April 2026, the Justice Department and the DEA placed FDA-approved drug products containing marijuana, and marijuana products covered by a qualifying state medical marijuana license, in Schedule III. All other marijuana, including recreational use, remains in Schedule I. A broader proposal to move all marijuana to Schedule III went to a DEA hearing that began on June 29, 2026, and had not been decided as of October 2026.
Because recreational marijuana is still illegal under federal law, many employers remain reluctant to employ people who use it, even where state law allows it. Some jurisdictions, such as the District of Columbia, have their own rules that differ from federal policy, particularly for medical users whose use does not cause impairment.
State laws generally let employers limit marijuana use where work is concerned, and employers in states that have legalized it have set their own restrictions.
The most common condition is medical certification: an employee who uses medical marijuana may be asked to show a prescription or record during hiring. Employees with a medical condition then receive a proper assessment of that condition and of their use of the drug.
Employers also write policies from a “safety-sensitive” point of view. Medical marijuana use must not create problems in safety-sensitive work, and it must not affect productivity or work ethics.
However legal marijuana may be in some states, federal law does not stop those states from setting their own rules on marijuana and the workplace. States that have legalized it generally let employers restrict use where there is a compelling reason. Many employers in these states closely review employees who use medical marijuana, while others have chosen not to regulate it at all.
In these states, employers usually weigh several factors:
Since legalization, there have been cases where patients were prescribed marijuana with a higher THC level than their condition required. This can cause other effects on top of the condition being treated. Doctors in states where it is legal need to assess each patient’s exact needs and tolerance for THC, because too much or too little can harm the patient’s health.
Even where medical marijuana is legal, employers commonly use tests such as oral fluid tests to check for THC.
As state laws continue to change, employers keep writing their own marijuana policies. The basic rule stays the same: act, including firing an employee, only after careful review. The level of impairment caused by marijuana and its effect on work should be the deciding factor in any legal decision about an employee.