The U.S. Supreme Court case Hein v. Freedom From Religion Foundation, Inc., 2006 revolved around the issue of taxpayer standing in lawsuits challenging federal funding for religious activities. The Freedom From Religion Foundation (FFRF) sued Jay F. Hein, Director of the White House Office of Faith-Based and Community Initiatives, arguing that using federal funds to support faith-based initiatives violated the Establishment Clause of the First Amendment which prohibits government endorsement or promotion of religion. However, the Supreme Court ruled in favor of Hein by a 5-4 vote stating that taxpayers do not have standing to challenge executive branch programs just because they are funded by general revenues; this is different from legislative appropriations where taxpayers might have such standing as per Flast v Cohen (1968). This decision effectively limited who could sue over alleged violations involving separation between church and state.

In the dissenting opinion for Hein v. Freedom From Religion Foundation, Justice David Souter argued that taxpayers should have standing to challenge executive branch programs on Establishment Clause grounds, just as they do with legislative ones. He disagreed with the majority's distinction between Congressional and Presidential spending, arguing it was not constitutionally significant in this context. Souter contended that if a taxpayer can challenge a congressional appropriation alleged to violate the Establishment Clause, then they should also be able to challenge similar expenditures made by the Executive Branch without explicit Congressional approval. The justice believed that such an interpretation would better uphold constitutional principles of separation of church and state while preventing potential abuses of power by any one branch of government.