Please use this link to access this publication. Abstract Background Wider availability of cannabis through medical and recreational legalization (MCL alone and RCL+MCL) has been hypothesized to contribute to reductions in opioid use, misuse, and related harms. We examined whether state adoption of cannabis laws was associated with changes in opioid outcomes overall and stratified by cannabis use. Methods Using National Survey on Drug Use and Health (NSDUH) data from 2015 to 2019, we estimated cannabis law associations with opioid (prescription opioid misuse and/or heroin use) misuse and use disorder. All logistic regression models (overall models and models stratified by cannabis use), included year...