At the conclusion of its 2001-2002 term, the Supreme Court issued its opinion in Zelman v. Simmons-Harris, a 5-4 decision that rejected an Establishment Clause challenge to the Cleveland, Ohio, school voucher program. Chief Justice Rehnquist’s majority opinion was straightforward, describing the decision as compatible with “an unbroken line of decisions rejecting challenges to similar programs.” Justice Thomas’ concurring opinion, however, was more far-reaching, questioning “as a matter of first principles . . . . [w]hether and how [the Establishment] Clause should constrain state action under the Fourteenth Amendment.”