A Colorado judge ruled Friday that consumers and sellers of recreational pot must continue to pay taxes, even if it puts them at risk of federal prosecution.

A group of marijuana activists had filed a lawsuit against the state, claiming that pot taxes violated consumers’ and businesses’ Fifth Amendment rights against self-incrimination.

The activists’ attorney, Rob Corry, warned that those who pay the taxes are essentially acknowledging that they have violated federal law.

“These taxes are a gift-wrapped open-and-shut federal prosecution,” Corry said during the nearly day-long hearing.

Individuals over the age of 21 are allowed to buy marijuana in Colorado, as well as Washington, though it remains illegal under federal law. The federal government has said it won’t block legalization on the state level.

Denver District Court Judge John Madden ruled that the activists did not present a clear enough case to strike down the taxes. None of the plaintiffs owned businesses or could point to consumers who had faced federal prosecution.

“Getting rid of the taxes is not going to prevent the federal government from prosecuting,” said Charles Solomon, a state attorney.

Corry argued that business-owners and customers did not want to take the stand because they feared that it would also put them at risk of arrest.

Marijuana taxes have been a major reason that lawmakers in Colorado and Washington have supported legalization. Colorado brought in more than $12 million in taxes since it legalized pot in November, with state officials predicting at least $30.6 million over the next fiscal year.