MADISON, Wis. (AP) — U.S. Agriculture Secretary Tom Vilsack says federal law bars the drug testing of food stamp recipients that Wisconsin plans. Vilsack responded Wednesday to a lawsuit filed by Wisconsin Attorney General Brad Schimel asking a federal judge to declare that state budget provisions requiring food stamp recipients to undergo drug testing are legal. In a statement, Vilsack says Congress has “repeatedly rejected the expensive, intrusive practice of suspicion-less drug testing,” which Vilsack says has been shown to uncover “very little drug use.” The USDA has not yet seen Schimel’s lawsuit, which was filed Tuesday. The budget Republican Gov. Scott Walker signed Sunday contains language requiring food stamp recipients to undergo drug screening. If they fail the screen they must go through drug testing and treatment to remain eligible for the benefit.