The Professional and Amateur Sports Protection Act (PASPA), which Congress passed in 1992, forbids states from “authorizing” sports betting “by law.” As every middle-schooler learns, however, our Constitution establishes dual sovereignty between the states and the federal government. And as the Supreme Court most recently held in New York v. United States (1992) and Printz v. United States (1997), the Constitution forbids Congress from “commandeering” state officials to serve federal ends, whether by forcing states to enforce federal laws or to pass new state laws (or to refrain from repealing old ones), which is exactly what PASPA does. In 2011, New Jerseyans voted overwhelmingly—two to one—to legalize sports betting in a 2011 referendum. The next year, the state legislature responded to the will of the people by enacting a law allowing sports wagering at casinos and racetracks. The four major professional sports leagues, plus the National Collegiate Athletic Association (NCAA), sued under PASPA to prevent the state from moving forward and legalizing sports betting. In 2016, the U.S. Court of Appeals for the Third Circuit ruled for the NCAA, reasoning that if the state were to repeal its pre-PASPA sports gambling laws, they would be “authorizing” the activity “by law,” which was forbidden by PASPA. Unwilling to be forced to continue enforcement of a law overwhelmingly rejected by its populace, New Jersey appealed to the Supreme Court. Cato has now joined the Pacific Legal Foundation and Competitive Enterprise Institute on a brief (written by former Cato intern Jonathan Wood) in support of the Garden State. We argue that PASPA unconstitutionally commandeers state officials and undermines the core concepts of federalism. If the federal government wants to enforce its chosen policy, it must find a way to do so that doesn’t involve having New Jersey do its dirty work. There are several options: Congress could regulate sports betting itself (at least across state lines) or it could use its spending power to provide incentives to states to adopt more restrictive schemes. Instead, PASPA forces states to enforce and maintain policies which have become outdated and unpopular, against popular and state sovereignty. PASPA and other overweening federal laws pose a serious problem for accountability because they tie the hands of state officials, forcing them to enforce policies they do not want. The people of the state then blame state officials for bad outcomes, not knowing that their hands are tied by Congress. Moreover, the same issue comes up again and again, in areas ranging from immigration to guns, from health care to marijuana. The federal government should not be forcing one-size-fits-all solutions on a large and diverse country—and indeed the Constitution was designed to prevent such abuse.