The school voucher question in the United States received a considerable amount of judicial review in the early 2000s.
A program in the city of Cleveland authorized by the state of Ohio was challenged in court on the grounds that it violated both the federal constitutional principle of separation of church and state and the guarantee of religious liberty in the Ohio Constitution. These claims were rejected by the Ohio Supreme Court, but the federal claims were upheld by the local federal district court and by the Sixth Circuit appeals court. The fact that nearly all of the families using vouchers attended Catholic schools in the Cleveland area was cited in the decisions. In a 2002 ruling in the case Zelman v. Simmons-Harris, the Supreme Court of the United States ruled in a 5-4 vote that the Ohio program was Constitutional. The justices cited the private choice made by the parents and affirmed that the ultimate purpose (improving elementary education) was secular.
The Florida Supreme Court on January 5, 2006 struck down laws that allowed for school vouchers in Florida.
Political support for school vouchers in the United States is mixed. On the left/right spectrum, conservatives are more likely to support vouchers. According to the National Education Association (NEA), a U.S. teachers union and the largest labor union in the country, "(U.S.) Voters, for the last 30 years, have rejected vouchers every time they've been proposed". However, some state legislatures have enacted voucher laws. As of 2006, the federal government operates the largest voucher program, for evacuees from the region affected by Hurricane Katrina.