Christina Semmer is an employment and business lawyer who counsels employers regarding Proposition 64 and workplace drug policies. She practices law at Wilson Turner Kosmo, LLP, the largest certified women-owned law firm in San Diego.

Attorney Christina C.K. Semmer

Here, she answers some common questions about what prospective employers can ask of job applicants and how drug testing can be applied. To submit questions about civil or criminal law as applied to marijuana in California, email

Q: Can a prospective employer still ask an applicant about his/her marijuana use prior to being offered a job?

A. The short answer is “yes.” There are no specific laws that would prohibit an employer from asking this particular question. However, as an employment lawyer, I’ve never heard of employers asking prospective employees specifically, “Do you use marijuana?” That doesn’t mean it doesn’t happen, but I would counsel against it for several reasons.

First, the likelihood that the applicant would truthfully disclose his or her marijuana use is probably pretty low.

Second, if an employer wanted to know this information, it would make more sense to drug test the applicant after making a job offer (see Q&A question below).

Third, from a legal perspective, asking this question is somewhat risky. Employers can’t ask about an applicant’s health and medical history or whether the applicant has a disability. If an employer asked a job applicant “Do you use marijuana,” that isn’t, in and of itself, a question about the applicant’s medical history. However, if the applicant responds “Yes, I use it medicinally to manage my epilepsy,” the employer risks facing a disability discrimination lawsuit if it chooses not to hire that individual (with the applicant arguing that the employer’s decision not to hire him was based on his epilepsy).

Additionally, employers generally shouldn’t ask questions that might elicit information about past drug use because past addiction can be considered a disability in some circumstances where treatment has been or is currently being sought. Casual drug use (past or present) is not a disability, but you can see why most (smart) employers would want to avoid getting into this when a drug test is so much simpler.

Nonetheless, not all employers are sophisticated in these matters and you should prepare for the possibility that this question will come up. Just know that if you deny marijuana/illegal drug use (and yes, marijuana is still an “illegal drug” in the eyes of most employers because it is illegal under federal law) but later fail a post-offer/pre-employment drug test, the employer can rescind its offer for the additional reason that you lied during the application process.

So, perhaps the most practical advice I can give is avoid using marijuana if you know you will be applying for a job.

Q. Can employers test some of their employees for marijuana and not others?

A. Yes. Generally speaking, employers in California can drug test employees in several circumstances, which explains how and why certain employees can be selected for testing while others are not:

Pre-employment testing: Employers can conduct drug testing as a condition of employment after a job offer is made but before employment begins. While employers don’t necessarily need to test all prospective employees, the drug tests need to be conducted in a fair and consistent manner. In short, it’s OK for employers to drug test all prospective employees for a specific job classification (i.e., delivery drivers) but not other classifications (i.e., office personnel). It would not be OK for employers to selectively choose who in a specific job classification to test before employment begins.  

Once employment actually begins, there are greater restrictions on employer drug testing, and there is a balancing act between employees’ right of privacy and the employer’s obligation to provide a safe workplace. Nonetheless, drug testing is still generally permissible in the following situations:  

Post-accident testing: Many employers drug test after a workplace accident or injury, but current legal authority suggests that employers should only test where there is a reasonable possibility that drug use was a contributing factor and/or there was serious injury or property damage. Moreover, the employer should only test the employee responsible for the accident, e.g., the individual operating the heavy machinery, not the passenger.

Random drug testing: Employers can conduct random drug testing for employees in security- or safety-sensitive positions. In that case, for example, it would be fine for a bank to randomly select 10 percent of its private security guards for drug testing. The key here is that the selection of individuals (often done by an independent third party) has to be truly random.  (Note that random drug testing is prohibited in San Francisco unless there are reasonable grounds to suggest that the employee is a danger to others.)

Reasonable suspicion: Courts have generally been supportive of employers drug testing employees where they have a “reasonable suspicion” the employee is under the influence of drugs at work. The employer’s “reasonable suspicion” must be based on specific objective facts like smell, physical appearance (i.e., bloodshot eyes) and unusual behavior (i.e., frequent use of eye drops, paranoia, lethargy). Employers should provide supervisor training to ensure that reasonable suspicion testing is consistently and objectively implemented.

Note that the above summaries are generalizations regarding the state of the law and whether drug testing was appropriate in a specific circumstance is a fact-specific analysis. In addition, requirements for public-sector employers, employers with federal government contracts and individuals whose employment is governed by a Collective Bargaining Agreement may differ.

Disclaimer: This column is solely informational in nature and is not intended as legal advice.