On October 13, the Supreme Court of Minnesota barred an employee from getting reimbursed for medical marijuana treatment for a work-related injury.[1] Although the employee was entitled to reimbursement from her employer under state law, the court found that the Controlled Substances Act (CSA) preempted state law. The decision highlights the latest episode of tension between marijuana’s federal listing as a Schedule I controlled substance — which includes drugs with “no currently accepted medical treatment use”[2] — and states that have authorized marijuana for medical treatment.