California Laws on Drug Testing

California's constitution gives employees a right to privacy at work, but employers can still drug test in some circumstances.

By Lisa Guerin , J.D. UC Berkeley School of Law Updated 5/23/2024

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Has your California employer or prospective employer asked you to take a drug test? Federal law places few limits on employer drug testing: Although the federal government requires testing by employers in a few safety-sensitive industries (including transportation, aviation, and contractors with NASA and the Department of Defense), federal law doesn't otherwise require – or prohibit drug tests. For the most part, this area is regulated by state and local laws. California is one of the few states with a state Constitution that includes a right to privacy. That right extends not only to government employees, but to employees in private industry as well. California courts have held that this right is implicated by drug testing, but that doesn't always mean drug testing is illegal. Testing is judged on a case-by-case basis, balancing the employer's reasons for testing against the intrusion on the employee or applicant.

Drug Testing Rules for Job Applicants in California

California employers may require employees to pass a drug test as a condition of employment. As long as an employer tests all applicants for particular job positions and doesn't single out certain applicants based on protected characteristics (such as race or disability), courts have upheld this type of testing.

Drug Testing Rules for California Employees

When determining whether a drug test was legal, California courts balance the employer's reason for testing against the employee's legitimate expectation of privacy. California has recognized that employees start with a stronger claim here: Employees already have a job (and a work history the employer can use to evaluate their performance), which gives them more of a stake in the process and may give the employer less of a need to test.

An employer that has a reasonable suspicion that an employee is using drugs may be on safe legal ground in testing, provided that the suspicion is based on objective facts. Random testing is more controversial, although courts have upheld random testing for very safety-sensitive positions.

Drug Testing for Marijuana in California

Marijuana is legal in California for both medical and recreational purposes, but until recently employers could fire employees based on a positive test for marijuana.

A new state law, effective January 1, 2024, provides that employers cannot discipline, fire, or otherwise take adverse action against an employee solely on the basis of a positive test for marijuana. (Cal . Gov. Code § 12954 (2024)). Employees who are clearly impaired while on duty are not protected, however.

Drug Testing: Notice and Procedural Rights for California Employees

California statutes don't set up specific drug testing procedures and protocols. Because of the balancing test courts apply to drug tests, however, employers are more likely to prevail if they take steps to diminish employees' privacy expectations (for example, by adopting a written policy explaining when drug testing will be required).

Legal Claims Arising From Drug Testing

In addition to violating an employee's or applicant's constitutional right to privacy, drug testing may give rise to other legal problems. Here are some examples:

Contact an Employment Lawyer

If you've experienced adverse consequences at work due to a failed drug test, it might be worth contacting an employment law attorney to discuss your legal options. If the test was performed illegally, you might be entitled to job reinstatement or money damages.