Missouri counties can no longer tax marijuana sales if a municipality is already doing it.

The Missouri Eastern District Court of Appeals ruled Tuesday that it鈥檚 unconstitutional to also impose county sales taxes on marijuana products.

The court ruled in favor of Robust Missouri 3 LLC, a Florissant-based dispensary that argued St. Louis County and Florissant could not each collect a 3% tax.

鈥淭he plain language of [the constitution] is unambiguous,鈥� Judge John Torbitzky wrote in the unanimous opinion, reversing a lower court's ruling in May.

Since voters approved a constitutional amendment legalizing recreational marijuana in 2022, local governments and industry groups have debated in court over how marijuana should be taxed.

Cannabis industry groups say without a stacked county tax, customers in Missouri will save millions in taxes each month.

鈥淭oday鈥檚 ruling helps put $3 million back into the pockets of Missouri customers each month and will allow the industry to continue to contribute hundreds of millions each year in sales tax revenue to the state and our local communities,鈥� said Andrew Mullins, Missouri Cannabis Trade Association executive director.

St. Charles County will challenge the ruling by taking it to the Missouri Supreme Court.

鈥淲hen the County Council asked the voters to approve the tax, we heard nothing from anyone in the industry,鈥� said St. Charles County Executive Steve Ehlmann. 鈥淭his Constitutional amendment was written by the marijuana industry, and they could have made it clear counties were excluded but that would have created opposition to their proposal.鈥�

In April 2023, 72% of voters in St. Charles County approved a 3% county tax on marijuana sales. In St. Louis County, 65% did.

St. Louis County spokesperson Doug Moore said the county is reviewing the ruling to determine next steps. Ehlmann said he expects St. Louis County to join the appeal.

鈥淚t is unclear at this point what the financial impact would be,鈥� Moore said.

This story has been updated with comments from St. Charles County Executive Steve Ehlmann.

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