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Medical Marijuana in Workers’ Compensation Cases

Tuesday, June 11, 2019

By Ryan Locke, Associate at Hennessy & Roach P.C.

As of May 10, 2019, 33 states and the District of Columbia had legalized the use of marijuana for medical purposes. German Lopez, Marijuana is Legal for Medical Purposes in 33 States, Vox (May 10, 2019 6:18 PM)   Not only has the State of Illinois been among these 33 states since 2013, but on May 31, 2019, the Illinois Legislature passed HB 1438 becoming the 11th state to legalize recreational use of marijuana. Elizabeth Campbell, Illinois Becomes 11th State to Legalize Recreational Marijuana, Bloomberg (May 31, 2019 3:01 PM)  This nationwide trend of legalizing/decriminalizing the use of marijuana has led many employers to question its consequences with regard to workers’ compensation cases.  This article seeks to answer those questions by focusing on the two areas where marijuana legalization will have the most substantial effect: (1) Intoxication in the workplace and (2) Employers’ liability for medicinal marijuana in compensable claims.


First, Section 11 of the Illinois Workers’ Compensation Act states, no compensation shall be payable if (1) an employee’s intoxication is the proximate cause of the accident or (2) the employee was so intoxicated at the time of the accident as to constitute a departure from his/her employment.  820 Ill. Comp. Stat. Ann. 305/11.  Further, evidence of impairment due to the unlawful or unauthorized use of marijuana creates the rebuttable presumption that the employee’s intoxication was the proximate cause of the work accident. Id.

Simply stated, just as with alcohol, if an employee is intoxicated/high on marijuana at the time of the accident, it is presumed the employee’s intoxication is the cause of the accident.  While this presumption may be overcome by Petitioner, it essentially creates another element of compensability for a Petitioner to prove – that s/he was not intoxicated at the time of the accident.   However, a problem arises for employers with the ability to assess a marijuana user’s level of impairment.  At this point, it is nearly impossible to assess a marijuana user’s level of impairment.   Urine testing is unable to discern recent use from weeks earlier and often cannot capture use that happened within the last few hours. (Marijuana in the Workplace, Occupational Health and Safety, (March 1, 2019),  Oral fluid testing has been recognized as the best practice by Occupational Health and Safety as it can detect recent marijuana use, exclude long past use, and do so with a noninvasive test.  Id.

It is important to note under Section 11 of the Act the rebuttable presumption that an employee’s intoxication was the proximate cause of the work accident is created only when the evidence of impairment is due to unlawful or unauthorized use of marijuana.  It may be argued intoxication due to use of prescribed medical marijuana would not be entitled to the rebuttable presumption.  We believe this is an incorrect interpretation.  Section 10-50 of the Cannabis Regulation and Tax Act provides specific protections to employers including the right to adopt reasonable zero tolerance or drug free workplace policies.  It is our belief the violation of any such policy would be “unauthorized” under Section 11 of the Workers’ Compensation Act.  Still, if an employee is able to return to work but has been prescribed medical marijuana, the employee and employer should take the same precautions as with any other medication with intoxicating side effects – such as pain management medication – to insure an employee is not intoxicated while performing his or her work duties.  

Liability for Costs of Medicinal Marijuana

Breathe easy.  Employers in Illinois, simply, are not liable for the costs of medicinal marijuana under the Illinois Workers’ Compensation act.  The Compassionate Use of Marijuana Act, which legalizes the use of marijuana for medical purposes, explicitly states, “Nothing in this Act may be construed to require a government medical assistance program, employer, property and casualty insurer, or private health insurer to reimburse a person for costs associated with the medical use of cannabis.”

Many states have similar laws allowing employers to refuse to pay for medical marijuana regardless of its reasonableness and necessity to treat a state of illness caused by a compensable work accident.   In addition, all States are also subject to federal law.  At the federal level, marijuana remains illegal in its classification as a Schedule 1 substance under the Controlled Substances Act.   Therefore, in addition to any applicable state laws, employers objecting to payment for medical marijuana should also cite marijuana’s prohibition under the federal Controlled Substances Act.


  1. Given marijuana use for not only medicinal, but recreational purposes is expected to be legal in Illinois as soon as January 1, 2020, employers should implement clear drug-free workplace policies.  Further, it is recommended employers also implement a drug testing policy to include oral marijuana testing following workplace accidents when intoxication of the employee is reasonably suspected by the employer or the accident involves something other than a repetitive strain or a late notice claim for which drug testing is of limited use.
  2. Employers should categorically deny payment for medical marijuana in conjunction with compensable workers’ compensation cases.  As marijuana remains illegal under the Controlled Substances Act, employers could be criminally prosecuted for providing such benefits.  Illinois law provides protections for employers denying such benefits.  However, utilization reviews could also be beneficial and allow employers to present multiple defenses to any litigation on the issue.   

 Ryan Locke is a associate at Tressler LLP in their Workers’ Compensation Department and can be reached at or 312-327-0151.

Material posted on this website is for informational purposes only and does not constitute a legal opinion or medical advice. Contact your legal representative or medical professional for information specific to your legal or medical needs.

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