Attorney General Jeff Sessions has rescinded an Obama-era policy that paved the way for legalized marijuana to flourish in states across the country, creating new confusion about enforcement and use just three days after a new legalization law went into effect in California. Instead of the previous lenient-federal-enforcement policy, Sessions’ new stance will instead let federal prosecutors where marijuana is legal decide how aggressively to enforce longstanding federal law prohibiting it. Republican Sen. Cory Gardner of Colorado, one of eight states that have legalized marijuana for recreational use, said in a tweet that the Justice Department “has trampled on the will of the voters” in Colorado and other states.