What standard of proof should the government meet to impose sanctions on an individual licensed by the state to practice his chosen profession? In a series of decisions this decade, the Supreme Court of Washington State required the government to prove facts constituting “unprofessional conduct” by clear and convincing evidence. Dissenters argue that, as a result of these decisions, “some of the state’s most vulnerable citizens are now even more at risk for abuse.” But there has been little empirical evidence to back these claims. Indeed, legislatively mandated biennial reports on the professional disciplinary process in Washington demonstrate that the higher burden of proof has had little effect on the imposition of licensing sanctions in the state...