On Friday, the U.S 7th Circuit Court of Appeals, by a vote of 2-1, held that taxpayers have standing to bring an Establishment Clause claim challenging Executive Branch spending on conferences to promote President Bush's "Faith-Based and Community Initiatives." At issue in Freedom From Religion Foundation, Inc. v. Chao (7th Cir., Jan. 13, 2005) was the question of whether taxpayer standing extends to situations in which there is no specific earmarking of funds by Congress for the challenged activity, and instead the spending comes from a general appropriation by Congress. Judge Posner wrote the majority opinion, and Judge Ripple dissented.
UPDATE: Here is further discussion and analysis of the case by Profs. Ira Lupu and Robert Tuttle.
