Since January 1, 2024, California law has protected employees and job applicants from discrimination based on their off-duty cannabis use. While employers can still enforce drug-free workplace policies, AB 2188 added Government Code section 12954 to limit how and when cannabis testing can be used, and what kind of tests are permissible.
These changes mark a significant shift in how employers should approach drug screening, workplace safety, and hiring decisions. Employers should take steps now to ensure their policies and practices align with the law.
Legal Background
AB 2188, which amended the Fair Employment and Housing Act (FEHA), made it unlawful for most employers to fire, refuse to hire, or penalize individuals for using cannabis outside of work. However, “the building and construction trades” and positions requiring testing under state and federal law are exempted from this prohibition.
The law prohibits employment decisions based on a drug test that detects nonpsychoactive cannabis metabolites. Nonpsychoactive cannabis metabolites are chemical traces that can remain in the body long after cannabis is used and do not indicate current impairment.
AB 2188 focuses drug testing on current impairment rather than past use. In this context, the distinction between psychoactive THC (which can impair performance) and its non-psychoactive metabolites (which do not) is crucial.
This means that traditional drug tests like urine or hair follicle tests, which detect only past cannabis use, are no longer sufficient grounds for termination or disciplinary action. Instead, employers must rely on testing methods that can detect active THC, such as oral fluid or breath-based tests, which are better indicators of recent use and potential impairment.
Importantly, employers are still allowed to maintain a drug-free workplace. They can prohibit the use, possession, or impairment of cannabis during work hours or on company property. Drug testing is still permitted, particularly in situations where there is reasonable suspicion of impairment on the job, workplace accidents, or when required by law. However, testing must be conducted carefully and with the right tools and procedures that comply with current legal standards.
Exceptions and Federal Considerations
AB 2188 includes exceptions for specific roles. The law does not apply to employees in the building and construction trades or to those in positions requiring a federal background check or security clearance.
It also does not override federal requirements, such as those imposed by the U.S. Department of Transportation (DOT), which still mandate drug testing for THC regardless of state protections.
Federal preemption means that California employers operating under federal contracts or in federally regulated industries must continue to follow applicable federal rules. In these contexts, a positive THC test, regardless of on-the-job impairment, may still disqualify the individual from employment. While the federal government has approved saliva testing for THC as an alternative to urine testing in DOT-regulated roles, no certified lab is currently approved to process these tests. As a result, DOT-covered employees are still subject to urine tests, which can detect cannabis use long after any impairment has ended.
Practical Implications for Employers
Employers must ensure their drug testing practices and policies comply with the laws protecting employees and job applicants from discrimination based on their off-duty cannabis use. This includes working with testing providers to ensure they are using screening methods that detect only active THC, which may indicate current impairment—not non-psychoactive metabolites, which simply reflect past use.
Pre-employment cannabis testing remains lawful only if it uses valid testing methods and occurs after a conditional offer has been made. Using outdated methods such as standard urine or hair tests may lead to unlawful discrimination claims if used to reject applicants or discipline employees.
Employers should also ensure that job applications and interview questions do not seek information about cannabis use, in line with SB 700, which prohibits employers from asking applicants about prior cannabis consumption.
For current employees, drug testing based on reasonable suspicion is still permitted. However, courts have made clear that such testing must be grounded in specific, observable conduct, such as erratic behavior or unsafe conduct, and balanced against an employee’s constitutional right to privacy under California law. Blanket or random testing is only allowed for safety-sensitive roles and should be avoided in other contexts.
Finally, employers should train managers to recognize signs of impairment and document their observations clearly. Because impairment assessments are highly fact-specific, especially with cannabis, having consistent procedures, documentation tools, and supervisor training in place is key.
Employer Takeaways
California’s cannabis laws have changed, but employers still have the right to maintain safe, productive workplaces. To stay compliant, employers should:
- Work with testing labs to ensure the tests detect active psychoactive metabolites—not non-impairing metabolites.
- Avoid basing employment decisions on off-duty cannabis use or test results that reflect past use only.
- Update job applications and interview protocols to avoid cannabis-related inquiries.
- Train managers on how to identify and document reasonable suspicion of impairment.
- Be mindful of federal requirements and exempt positions that fall outside of AB 2188.
As this area of the law continues to evolve, employers should consult legal counsel before implementing a testing program which includes testing for cannabis use or acting on test results. With careful planning and updated policies, employers can maintain compliance while preserving workplace safety.
