California has always been at the forefront of cannabis regulation. Medical marijuana was legalized nearly three decades ago, and Proposition 64 made recreational use lawful in 2016. But legalization for personal use has never meant unlimited rights in the workplace. Until recently, employers had broad discretion to take action against applicants or employees who tested positive for cannabis—even if the use was off-duty and had no impact on job performance. That changed on January 1, 2024, when two new laws, AB 2188 and SB 700, took effect and significantly changed the rules in this area.

The New Legal Landscape

Under AB 2188, California employers may no longer discriminate against individuals simply because they use cannabis on their own time and away from the workplace. The law prohibits employers from relying on tests that detect only “non-psychoactive cannabis metabolites”—that is, chemical traces that can remain in a person’s body for days or weeks after use, long after any impairment has subsided. This development is a significant shift from past practice, when a positive cannabis test often meant automatic rejection of an applicant or discipline of an employee, regardless of whether the individual was impaired.

SB 700 complements AB 2188 by prohibiting employers from asking applicants about their past cannabis use. Taken together, the two laws make clear that California workers are entitled to some privacy when it comes to legal, off-duty activities. However, neither law allows cannabis possession or use in the workplace or prevents employers from taking corrective action when an employee is impaired at work. Employers still have every right—and, in many cases, a legal obligation—to ensure a safe, drug-free environment.

Important Exceptions

The new protections are not absolute. Certain industries and roles remain outside the reach of AB 2188. For example, positions that require federal security clearances or background checks remain subject to federal drug-free workplace rules. The construction trades also enjoy a special exemption that allows employers to continue testing for cannabis metabolites. And nothing in the new laws limits an employer’s ability to prohibit use or possession of cannabis on the job. The state has drawn a clear line: off-duty use is protected in most cases, but impairment during work is not.

What Employers Should Do Now

For California employers, these developments mean workplace policies and practices must be updated. Drug-testing programs that rely on outdated methods risk violating the new law. Handbooks should be revised to reflect the distinction between off-duty use and on-the-job impairment. Supervisors need training to recognize potential signs of impairment and to respond in a way that is consistent, defensible, and respectful. Employers also should communicate these changes to employees, so everyone is clear about the workplace expectations.

At the same time, employers must remain alert to situations where federal law or safety concerns demand stricter standards. For example, multistate employers face the added challenge of balancing California’s rules with different requirements in other jurisdictions.

What Employees Need to Understand

Employees should recognize that although the law now protects lawful cannabis use away from work, it does not grant unlimited freedom. Showing up impaired, using cannabis during work hours, or bringing cannabis to the workplace remain legitimate grounds for discipline. Employees in federal or safety-sensitive roles may not enjoy the same protections as others. The bottom line: off-duty use is shielded, but workplace performance and safety still control the employer’s response.

Looking Ahead

The new cannabis protections reflect a broader trend in California toward respecting employees’ rights to engage in lawful off-duty conduct. At the same time, the laws leave many questions unanswered, particularly around what counts as “impairment” and how employers can prove it. Litigation likely will shape these boundaries in the years to come. For now, the safest path is for employers to update policies, train supervisors, and ensure consistent enforcement. Employees, for their part, should stay informed about their rights while recognizing their ongoing responsibility to remain fit for duty.

Still confused? Join us for our webinar, “High Stakes: Navigating California ‘s New Cannabis Workplace Rules,” on September 23, 2025, at 9:00 a.m.  As always, we will discuss best practice and answer all of your questions.  Register here!

About Shaw Law Group 

At Shaw Law Group, we do more than practice employment law—we partner with employers to build compliant, respectful, and productive workplaces. From day-to-day advice and counsel to impartial workplace investigations, proactive HR audits, dynamic training programs, and sensitive pre-litigation matters, our experienced team helps clients stay ahead of the curve—and out of court.