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Medical Cannabis Laws: What Do They Mean for Workplace Safety?

Sep 22, 2023
Cannabis growing in a greenhouse

As medical cannabis use expands in states across the U.S., and signs point toward federal legalization in the future, safety professionals must know the implications for workplace safety.

Not only are more states legalizing medical cannabis, but more doctors are also prescribing it rather than heavy-duty pain-relief options like opiates. As adoption and use increases, more cases come up in the courts about how to address medical cannabis in the workplace, prompting many states to reevaluate their laws as the landscape evolves.

This leaves employers and safety professionals operating under a patchwork of laws, policies and requirements, from their state legislatures to OSHA to the Americans With Disabilities Act (ADA).

Diving into this legally gray area, Adele Abrams, Esq., ASP, CMSP, highlighted cannabis laws, relevant cases, policy developments and workplace trends in a webinar titled “Medical Cannabis and Workplace Safety,” presented by our Consultants Practice Specialty and Blacks in Safety Excellence (BISE) Common Interest Group.

Considerations for Medical Cannabis and Workplace Safety

A 2017 federal case highlights “how a company can really do everything wrong” in regard to these issues, Abrams says. A Washington-based employer fired an employee for testing positive for the opioid Dilaudid, which was legally prescribed to treat migraines. The company claimed she was working impaired in a “safety-sensitive” position, leading to a “reasonable suspicion” drug test and her eventual termination.

But the court didn’t find evidence of impairment or any real reason for her supervisor to suspect it. The court also disagreed that her customer sales representative role was safety sensitive.

Instead, the court determined the “employer should have treated her as an employee with a medical condition, rather than as a drug abuser,” Abrams says.

While this case was about opioids and not medical cannabis, it provides several relevant lessons:

  1. Employers should treat medical cannabis users as employees with medical conditions and make necessary accommodations.
  2. Not every position is safety sensitive and employers cannot simply claim any position as such.
  3. Supervisors hold a lot of responsibility for identifying impairment.

The case also highlights how employers must walk the line between honoring workers’ legal protections and protecting workers.

“When it comes to OSHA, we have a bit of a tension here because OSHA can cite an employer on the General Duty Clause if the employer fails to protect workers from ‘direct threats to safety,’” Abrams says. “Most of us would agree that someone who is under the influence of alcohol or drugs poses that kind of recognized threat.”

This makes the case for measures such as drug testing as a tool for identifying impairment. However, OSHA also says drug testing can have “a chilling effect on workers reporting their injuries accurately,” Abrams says.

As a safety professional, ensuring drug testing is used fairly and that supervisors are trained to properly identify impairment addresses these key workplace safety issues — and avoids the kinds of errors the Washington company made that led to a $1.8 million judgment against them.

How to Define and Identify Impairment

Determining impairment is a critical part of protecting workplace safety when employees may be using medical cannabis, but it can be tricky to define. There is no defined “legal limit” of consumption, such as the blood/breath alcohol concentration, past which users can be considered “under the influence” or impaired.

That’s why some lawmakers have attempted to define cannabinoid impairment. According to the Illinois Compassionate Use of Medical Cannabis Act, someone is impaired when they manifest specific, articulable symptoms while working that impede their performance of the duties or tasks of their job, including:

Symptoms of the employee's speech, physical dexterity, agility, coordination, demeanor, irrational or unusual behavior, negligence or carelessness in operating equipment or machinery, disregard for the safety of the employee or others, or involvement in an accident that results in serious damage to equipment or property, disruption of a production or manufacturing process, or carelessness that results in any injury to the employee or others.

While this is not conclusive, it offers a starting point for defining impairment.

The best way to identify impairment and, therefore remove someone who is not able to safely perform their job, is through supervisor training, Abrams says. Supervisors should:

  • Be able to recognize impairment through reasonable suspicion training, including the kind of documentation and follow-up required.
  • Be informed on how to identify an addiction-related problem in advance of a catastrophic event, as well as how to get help for addicted workers.
  • Take workers who are suspected of being “under the influence” to a private area with a second supervisor to witness and document any action or statements.
  • Notify senior management of these events.
  • Be willing to suspend a worker until investigation can take place and/or until the worker completes treatment or is evaluated by the company employee assistance program.

Observations made of the employee exhibiting signs of impairment must be articulable and documented by a supervisor who has participated in training on the signs and symptoms of substance abuse and the requirements for reasonable suspicion testing, Abrams says.

Drug Testing When Medical Cannabis Is Legal: The New Rules

While drug testing is allowed in all 50 states, it’s important to consider several developments related to medical cannabis. While safety professionals don’t usually get involved in drug testing as a term of employment or random testing (that’s a job for HR), there are some ways that safety professionals may touch on the use of drug testing in their organizations through reasonable suspicion or a safety incident.

Drug Testing Outside an Incident 

When a supervisor suspects an employee is impaired outside of any incident, reasonable suspicion drug testing is allowed, according to OSHA. However, Abrams recommends that it be conducted under a written program that includes the following:

  • A written rationale
  • Detailed prohibited behaviors (the kind that might trigger a drug test)
  • Substances covered
  • Employees subject to the policy
  • Consequences of policy violation (second chance, rehabilitation, termination)
  • The method of testing (urine, hair, mouth swab)
  • Availability of assistance for those who test positive

Some states’ medical cannabis laws, even municipal laws, more narrowly define when you can test, especially in non-safety-sensitive positions, Abrams adds.

Drug Testing When an Incident Occurs 

When a safety incident occurs, proceed with extreme caution, Abrams advises. Documentation should be thorough.

According to OSHA rules, employers cannot drug test an employee solely because they were injured. However, employers can conduct drug testing to evaluate the root cause of a workplace incident that harmed or could have harmed an employee.

If you choose to drug test as part of an investigation, you should test all employees whose conduct could have contributed to the incident, not just employees who reported injuries, Abrams says.

Consider this example: If a forklift driver hits a warehouse worker with a forklift causing injury, the warehouse worker’s impairment is not likely relevant and it might be viewed as retaliatory to require a drug test. However, the forklift driver’s impairment is relevant, as may be the impairment of the mechanic who recently repaired the equipment. An employer can test both employees as part of a root- cause investigation.

There is an option outside of drug testing called “fit for duty” testing. Rather than testing for specific substances, these tests look for impairment for any reason, including conditions such as fatigue and stress. While these may not be appropriate for Department of Transportation (DOT) or critical safety positions, they can ensure workers in many positions are not impaired without potentially causing discrimination of cannabis users.

Medical Cannabis and Workplace Safety: What to Do Now

As medical cannabis laws continue to change throughout the U.S., employers and safety professionals must stay on top of them. Abrams suggests taking these high-priority steps:

  • Check your current drug testing program against the new OSHA rules and applicable state laws for your company and watch for changes in 2023.
  • Consider shifting away from drug tests and toward fit for duty tests, such as Druid or Sobereye. Make sure you are conforming with requirements that might apply under rules for government contractors, DOT and requirements under the ADA.
  • If in a union environment, make sure any policy is negotiated as part of the collective bargaining agreement as drug testing can be a term and condition of employment under the National Labor Relations Act.
  • Make sure supervisors are trained on identifying impairment.
  • Treat all employees fairly and do not treat injured workers in a disparate manner.

Above all: “Know the law in your state, read the law or talk to a lawyer in your state,” Abrams says.

She particularly advises those operating in states that allow use of recreational marijuana to pay particular attention to medical cannabis provisions, which often change alongside the legalization of recreational cannabis.

Often, these changes don’t make headlines until there is a case, she says, adding that “you don’t want to be the test case.”

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