Decision by Attorney General Jeff Sessions comes days after California became the latest state to permit sale of the drug for recreational use

Attorney General Jeff Sessions Thursday rescinded Obama-era policies that took a largely hands-off approach to enforcing federal marijuana laws in states that have legalized the drug for medical or recreational purposes. In a single-page memo, Mr. Sessions called the previous guidance “unnecessary” and permitted U.S. attorneys to take a more aggressive approach to enforcing laws on marijuana trafficking and use. Justice Department officials said the previous guidance wasn’t consistent with federal law.

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