December 9, 2022

Stay Current: True or False? Drug Testing for Marijuana is About to Become Illegal in California

By Christine

By Bill Current, President and Founder, Current Consulting Group, LLC, home of Current Compliance, the industry’s only comprehensive on-line source for all state laws that affect drug testing.

Will California employers still be allowed to drug test for marijuana come 2024? Or will testing for marijuana essentially be banned in the golden state à la New York? 

Despite not previously having a dedicated state drug testing law, California has traditionally been a complicated state when it comes to screening applicants and employees for drugs. When combined, many years’ worth of precedent-setting case law (some dating back as far as 1994) have established the equivalent of an otherwise mandatory state law. When testing is allowed and some aspects of how testing can be conducted have been governed for years by a variety of court decisions. However, that may be changing, in part, because of a new law that goes into effect in January 2024. 

Bill AB-2188 vs. Science

On September 19, 2022, Governor Gavin Newsom signed AB-2188 (the Bill), which provides protections for off-duty cannabis use by Californians. However, in an attempt to protect marijuana users, the Bill takes direct aim at workplace drug testing. In fact, a headline that ran in the Sacramento Bee declared “California employers will soon be barred from testing employees for marijuana use.” And, this brings us to the true or false question. Before we get to that, however, let’s unpack a few assumptions cited in the bill that appear to have been used to justify the new law’s restrictions on drug testing. For instance, the Bill states: 

“Tetrahydrocannabinol (THC) is the chemical compound in cannabis that can indicate impairment and cause psychoactive effects. After tetrahydrocannabinol is metabolized, it is stored in the body as a non-psychoactive cannabis metabolite. These metabolites do not indicate impairment, only that an individual has consumed cannabis in the last few weeks.” 

In reality, marijuana-induced impairment and its duration is caused by various factors, including the THC-level of the marijuana consumed, how it is consumed (smoked vs. edibles), the frequency of use by the individual, and the task being performed (remembering instructions vs. operating heavy machinery). A recent report from the University of Sydney, which considered results from 80 studies from around the world, concluded that marijuana-related impairment lasts between 3 and 10 hours.iii This means that the detection of marijuana metabolites does not necessarily mean that the donor was not impaired at the time of the test. In fact, impairment can last well beyond the time in which a marijuana user no longer feels intoxicated by the drug. 

To take this one step further, the detection of a metabolite of marijuana does not automatically mean that the metabolite is nonpsychoactive. Remember, impairment from marijuana usage can last several hours. Also, the presence of a marijuana metabolite does not automatically mean that the use was weeks ago as the bill implies. In urine, a marijuana metabolite is detectable within about 6 or 7 hours after the initial usage, well within the average window of impairment of 3-to-10 hours per the Sydney report. 

The Bill continues:  

“The intent of drug tests is to identify employees who may be impaired. While there is consensus that an employee should not arrive at a worksite high or impaired, when most tests are conducted for cannabis, the results only show the presence of the nonpsychoactive cannabis metabolite and have no correlation to impairment on the job.” 

Again, this assumption is not supported by the science. See the explanation above. To say the presence of a “nonpsychoactive” cannabis metabolite” has “no correlation to impairment on the job” is unprovable and sounds like it came from a company’s marketing materials rather than a peer-review journal. Also, employers drug test for a variety of reasons besides identifying employees who are impaired, including deterring drug use, identifying people who need help, and to comply with contractual obligations or applicable laws. Drug test methods that identify the presence of marijuana metabolites help to accomplish those objectives. 

The Bill also states: “As science has improved, employers now have access to multiple types of tests that do not rely on the presence of nonpsychoactive cannabis metabolites. These alternative tests include impairment tests, which measure an individual employee against their own baseline performance, and tests that identify the presence of THC in an individual’s bodily fluids.” 

As we see once again, the authors of the bill were enamored with the word “nonpsychoactive,” which in and of itself is misleading as explained above. Second, yes, there are other types of tests that purport to identify impairment without detecting the presence of drugs. These “cause-agnostic” examinations hold tremendous promise and may become popular in time but do not represent a 100-percent replacement for drug testing. 

Based on these questionable assumptions, AB-2188 then declares that beginning in January 2024 it will be “unlawful for an employer to discriminate against a person in hiring, termination, or any term or condition of employment, or otherwise penalizing a person” if the discrimination is based upon, among other things, “An employer-required drug screening test that has found the person to have nonpsychoactive cannabis metabolites in their hair, blood, urine, or other bodily fluids.” 

The science of drug testing does not yield a result that distinguishes between a metabolite that is still active and one that is not, this so-called “nonpsychoactive” metabolite. Remember, marijuana-induced impairment varies from user to user, from episode to episode, and can last for up to 10 hours (or much longer according to some reports). But as the law is written, any drug testing method that solely identifies cannabis metabolites rather than the drug itself, often referred to as the “parent” drug, would not be permitted for pre- or post-hire testing for cannabis. As such, urine testing for cannabis would be banned in California except for industries or occupations specifically exempted from the law (i.e., an “employee in the building and construction trades.”).  

Federal Law

Despite the fact that the federal government has maintained extensive guidelines for all aspects of lab-based urine testing for more than 30 years, it would not be allowed due to California’s legalization of medical and recreational marijuana use. In an effort to protect the rights of marijuana users, the only drug testing method currently permitted by the U.S. Department of Transportation (DOT), one that has proven to be the gold standard of drug testing, would not be permitted in the state. (Note: Of course, the DOT regulations trump this new California law and DOT-covered employers would still be required to conduct lab-based urine testing for all covered drugs, including marijuana.) 

On February 28, 2022, DOT issued a Notice of Proposed Rulemaking for lab-based oral fluid testing. This followed the October 2019 issuance of mandatory guidelines for lab-based oral fluid testing by the Substance Abuse and Mental Health Services Administration (SAMHSA), the federal agency that governs government-required workplace drug testing.  

Why are these moves by the federal government important in light of California’s new restrictions on metabolite-detecting drug testing methods? Because oral fluid testing detects the parent drug and not just a metabolite. Identification of the parent drug means that cannabis becomes detectable in an oral fluid sample within minutes after a person smokes a joint or eats a THC-laced brownie. This means that if AB-2188 stands as signed by the governor, oral fluid testing will be the only legitimate testing method for which there are legally defensible government-issued standards permitted for cannabis testing in the state of California.  

It is also worth noting that, technically, hair testing is capable of detecting the parent drug as well as metabolites of marijuana. However, because of the 7-to-10-day lag time between the time marijuana is consumed before it becomes detectable in a hair sample, its use may be problematic in California vis-à-vis this new law.  

Keep in mind that the California Bill was written, presumably, to protect legal users of marijuana from discrimination in the workplace. Despite AB-2188’s faulty reasoning, if an employer conducts oral fluid testing, with its ability to detect the parent drug and also to detect use within minutes of the initial usage, a positive drug test result should be sufficient to claim that the person was impaired on the job, which, of course, is not necessarily true from a scientific perspective despite what this new law claims. 

The Bill also states that employees are not permitted to “possess, to be impaired by, or to use, cannabis on the job…” It further states that the new law is not intended to hinder “the rights or obligations of an employer to maintain a drug- and alcohol-free workplace, as specified in Section 11362.45 of the Health and Safety Code, or any other rights or obligations of an employer specified by federal law or regulation.” 

For your information, Section 11362.45 of California’s Health and Safety Code subsection (f)iv states that nothing in the state health code is intended to “amend, repeal, affect, restrict, or preempt”… “The rights and obligations of public and private employers to maintain a drug- and alcohol-free workplace or require an employer to permit or accommodate the use, consumption, possession, transfer, display, transportation, sale, or growth of cannabis in the workplace, or affect the ability of employers to have policies prohibiting the use of cannabis by employees and prospective employees, or prevent employers from complying with state or federal law.” 

Other California laws are likely to be impacted by and may possibly prove to be obstacles to AB-2188. For instance, California’s workers’ compensation regulation states that an injured worker is not entitled to benefits for an injury which is caused by the “unlawful use of a controlled substance of the injured employee.”v “Controlled substance,” according to the regulation, shall have the same meaning as prescribed in Section 11007 of the Health and Safety Code, which includes marijuana as well as synthetic Will that language be changed to take into account California’s new drug testing law?  

Drug Testing 

It is important to emphasize that no drug testing method can prove, either scientifically or legally, that a person is impaired. As previously stated, the technology of any drug testing method does not distinguish between active and non-active metabolites. No legitimate drug testing company would make such a claim about their product. It would also be highly misleading for anyone to claim that a result using their drug-test method more closely “correlates” to impairment versus other testing methods because the window of impairment varies so unpredictably from user to user, and the precise circumstances in which the use took place. 

Urine, hair and oral fluid testing have withstood the test of time, triumphed over legal challenges, and proven to be practical and cost-efficient on a day-to-day basis in the workplace, but their proponents do not claim that they prove impairment.  

AB-2188 also states: “As science has improved, employers now have access to… tests that identify the presence of THC in an individual’s bodily fluids.” This statement begs the question: To which scientific improvements in drug testing are the authors of the Bill referring? Urine, hair and oral fluid testing have been in existence for decades and have always been capable of identifying the “presence of THC in an individual’s bodily fluids.” However, none of the major laboratories or device manufacturers, as well as third-party administrators, claim that their drug testing product can conclusively identify impairment. 

Some advocates of marijuana legalization are fond of using the phrase “peak window of impairment,” suggesting that marijuana impairment only lasts about 2-3 hours, but generally much less than that and that beyond that so-called peak window of impairment it’s no longer an employer’s right to know if employees have detectable amounts of marijuana in their system. However, if marijuana impairment can last up to 10 hours as stated in the Sydney report, then a person is potentially just as impaired and dangerous behind the wheel of a delivery van, forklift or other heavy machinery at 9 hours and 30 minutes as he or she was at 1 hour and 30 minutes. 


Will more states follow California’s lead and make drug testing more difficult for employers to conduct? That is similar to the question we were asking in 2021 when the New York Department of Labor essentially banned all testing for marijuana in the workplace. California, despite using some very questionable reasoning, may have taken its own path, but its new law may end up at the same destination. 

This information is provided for educational purposes only. Reader retains full responsibility for the use of the information contained herein. 

Find the state drug testing law information you need when you need it. Ask NDASA how to subscribe to the Current Compliance, the drug testing industry’s only on-line, regularly updated, and fully searchable database of all state laws that affect workplace drug testing. Subscribe at a special NDASA Preferred Provider rate.

© 2010-2022 The Current Consulting Group, LLC – No portion of this article may be reproduced, retransmitted, posted on a website, or used in any manner without the written consent of the Current Consulting Group, LLC. When permission is granted to reproduce this article in any way, full attribution to the author and copyright holder is required. 

[showlibraryitem id=157]