US Attorney General Jeff Sessions announced [press release] Thursday that previous policies of non-interference with states that have legalized marijuana are “unnecessary” and called on US attorneys [memorandum] to enforce the Controlled Substances Act.

Sessions has indicated that US attorneys should begin prosecution of those who cultivate, distribute or possess marijuana, launder money, or in any other way break national laws prohibiting marijuana. In the memo, the attorney general called marijuana “dangerous” and activity surrounding the drug to be a “serious crime.”

Specifically, Sessions has invalidated former deputy attorney general David Ogden’s 2009 memo authorizing the medical use of marijuana, and former deputy attorney general James Cole’s memos giving guidance to medical enforcement, financial crimes and general enforcement [JURIST reports]. The abolished memos moved in a direction towards tolerance and non-interference.

This change raises questions of whether previously halted [JURIST report] raids of marijuana facilities might start up again. Additionally, Sessions’ memo might contradict United States v. McIntosh [opinion, PDF], in which the US Court of Appeals for the Ninth Circuit ruled against the enforcement of the Controlled Substance Act for medical marijuana.