Waltham, MA, April 30, 2025 – As more states adopt recreational marijuana laws (RMLs), a new study by the Workers Compensation Research Institute (WCRI) examines changes in workers’ compensation claim frequency and outcomes such as per-claim medical payments, indemnity benefits, temporary disability duration, and prescription drug utilization and costs.

"This research is important as marijuana use continues to rise," said Ramona Tanabe, president and CEO of WCRI. "Our study highlights the complex effects RMLs have on work injury risk and workers' compensation claim costs. This information is relevant for policymakers, insurance carriers, medical providers, labor advocates, and employers as they navigate these evolving challenges."

The study, Impact of Recreational Marijuana Laws on Workers’ Compensation Benefits, answers key questions:

• How did the adoption of RMLs affect overall workers' compensation claim frequency?
• Were the effects different among younger workers, or those in safety-sensitive or physically demanding jobs?
• What impact did RMLs have on medical payments per claim?
• Were there changes in prescription drug use due to RMLs, including opioids?
• Did RMLs affect indemnity benefits and disability duration?
• Did the impact of RMLs on these outcomes change over time?

The study’s findings can inform debates on issues such as marijuana rescheduling, occupational treatment guidelines, state THC (tetrahydrocannabinol) regulations, or marijuana taxes. The analysis covers 31 states, using data from workers' compensation claims filed between October 2012 and March 2022.

Click here for more information or to purchase a copy of the study. It was authored by Vennela Thumula, Johanna Catherine MacLean, David Powell, and Sebastian Negrusa.

ABOUT WCRI

The Workers Compensation Research Institute (WCRI) is an independent, not-for-profit research organization based in Waltham, MA. Organized in 1983, the Institute does not take positions on the issues it researches; rather, it provides information obtained through studies and data collection efforts, which conform to recognized scientific methods. Objectivity is further ensured through rigorous, unbiased peer review procedures. WCRI's diverse membership includes employers; insurers; governmental entities; managed care companies; health care providers; insurance regulators; state labor organizations; and state administrative agencies in the U.S., Canada, Australia and New Zealand.

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