Vermont on [May 8] became the first state in the nation to require the labeling of genetically engineered foods. Gov. Peter Shumlin signed that mandate into law on Thursday afternoon, saying in a statement we believe we have a right to know what's in the food we buy." The new law represents a significant victory for advocates who have for years pushed such measures at the state and local level. But there remains one more hurdle to overcome: a likely lawsuit. Legislators, officials and advocates are preparing for the state to be sued over the new law. Last month, state Attorney General Bill Sorrell told Vermont Public Radio that he would be "very surprised" if the state isn't sued. And officials were so sure of a challenge that the measure itself creates a $1.5 million legal defense fund, to be paid for with settlements won by the state. "The threat of a lawsuit worked for a while, but now it doesn't work anymore," says Ronnie Cummins, national director of the Organic Consumers Association, whose organization has for years worked with activists and lawmakers in Vermont on the issue. At least 25 states have considered such legislation, according to a recent report on labeling requirements from the nonprofit Council for Agricultural Science and Technology. And advocates are hopeful they will get a measure on the Oregon ballot this year. Proponents argue that the science behind genetically modified food is far from conclusive and ask why consumers should take risks without knowing what they're eating. If companies truly stand behind the safety of GMO foods, they shouldn't worry about having to identify them, advocates for labeling argue.