Scott Shupe was convicted last year on marijuana charges after police raided his dispensary and his mother's home.
In a 2-1 decision Tuesday, the appeals judges said police lacked probable cause to justify the searches, and that prosecutors could not overcome his argument that he was acting in accordance with Washington's medical marijuana law.
The Spokesman-Review reports that Shupe testified at trial that he was selling 10 pounds of marijuana a week to 1,280 patients. Within a week of his March 2011 conviction, federal authorities sent letters to all other dispensaries in the region, warning them to shut down. Most did, but others continued and wound up being indicted.
Washington's Initiative 502, legalizing up to an ounce of marijuana under state law, took effect last week but does not change the state's medical marijuana laws.