Idaho's governor signed a law Wednesday requiring the state's attorney general to sue the federal government over any mandate to require health insurance. The move leads the way in a states-rights backlash against potential legislation. According to the Associated Press, similar legislation is in the works in 37 states. Gov. Butch Otter conceded that law scholars believe that federal law will trump state law in a U.S. District Court case. "The ivory tower folks will tell you, 'No, they're not going anywhere,'" Otter said Wednesday. "But I'll tell you what, you get 36 states, that's a critical mass. That's a constitutional mass."