WASHINGTON — The Supreme Court wrestled today with the question of whether taxpayers have the right to challenge the White House's aggressive promotion of federal financial aid for religious charities.

At issue is whether a Wisconsin-based group of atheists and agnostics have legal standing, by virtue of being taxpayers, to bring their complaint in the federal court system.

Taking one extreme, Justice Stephen Breyer asked a lawyer for the White House whether a taxpayer would be able to challenge a law in which Congress sets up a church at Plymouth Rock.

"I would say no," responded Solicitor General Paul D. Clement, but he added that such a church could be challenged in other ways — just not on the basis that a taxpayer has been injured. Clement is representing the Bush administration, which is trying to prevent the taxpayer suit over its aggressive promotion, through the White House Office of Faith-Based and Community Initiatives, of federal financial aid for religious charities.

Taking the opposite extreme, Justice Antonin Scalia asked a lawyer for the Wisconsin group, Andrew Pincus, whether taxpayers would be able to sue over the use of security money for a presidential trip where religion is discussed.

Pincus said that taxpayers would not have standing to do so, arguing that in such a case the money spent would be "incidental," and not central to the issue.

The case may turn on a 1968 Supreme Court decision — Flast v. Cohen — that created an exception to the general prohibition on taxpayer challenges to the government spending of tax revenue. In an 8-1 decision authored by Chief Justice Earl Warren, the Court allowed taxpayers to challenge congressional spending for private religious schools.

But the Bush administration says spending for speeches and meetings of executive branch officials does not involve spending federal money outside the government and therefore taxpayers are not entitled to challenge it.

In the current case, the Bush administration organizes conferences where faith-based organizations are allegedly singled out as being particularly worthy of receiving federal money.

The group challenging the Bush administration, called the Freedom From Religion Foundation Inc., characterizes the White House's initiative as a singling out of faith-based organizations to the exclusion of other organizations.

Last year, a federal appeals court allowed the group to pursue its lawsuit. Instead of going through Congress, President Bush issued executive orders to create the White House office and similar centers in 10 federal agencies during his first term.

One of the goals Bush set for these offices was to help religious and community groups compete for federal funding to fight poverty, substance abuse and other social problems.

The 7th U.S. Circuit Court of Appeals in Chicago sided with the anti-religion group, and the Justice Department wants the Supreme Court to overturn the lower court.

The case argued today is Hein v. Freedom From Religion Foundation Inc., 06-157.