Without any comment, the justices let stand a federal appeals court ruling that placing the monument on government property would violate church-state separation under the U.S. Constitution's First Amendment.
Indiana argued in its appeal that the First Amendment permitted the government's display to "memorialize the role the Commandments have played in the development of the rule of law and of the American legal system."
The court's action leaves in place a hodgepodge of conflicting court rulings across the country that allow the Ten Commandments' display in some instances but not in others.
It was the second time in less than a year that the court sidestepped the Ten Commandments issue.
The Ten Commandments contain both religious and secular directives, including the familiar proscriptions on stealing, killing and adultery. The Bible says God gave the list to Moses.
The Constitution bars any state "establishment" of religion. That means the government cannot promote religion in general, or favor one faith over another. The Constitution also protects the freedom to worship.
Last May, the court divided bitterly over whether to hear another case testing whether a different Ten Commandments monument could be displayed outside a civic building. The court opted not to hear the case, but the three most conservative justices took the rare step of announcing that they would have agreed to hear it.
Chief Justice William H. Rehnquist, and Justices Antonin Scalia and Clarence Thomas then did something even more unusual. They staked a position on a case that was not even pending, by saying they found nothing wrong with the monument's display.
The monument "simply reflects the Ten Commandments' role in the development of our legal system," Rehnquist wrote for the three.
The monument then at issue had a secular as well as a religious purpose, Rehnquist wrote. By displaying the monument outside the building housing local courts and prosecutors, city leaders in Elkhart, Ind., sought to reflect the cultural, historical and legal significance of the commandments, Rehnquist wrote.
"Indeed, a carving of Moses holding the Ten Commandments, surrounded by representations of other historical legal figures, adorns the frieze on the south wall of our courtroom," he added. The carving "signals respect not for great proselytizers but for great lawgivers."
Justice John Paul Stevens, on the opposite ideological end of the court, laid his own cards on the table with a scolding reply. The words "I am the Lord thy God," in the first line of the monument's inscription are "rather hard to square with the proposition that the monument expresses no particular religious preference," Stevens wrote then.
It takes the votes of at least four of the nine justices to agree to hea a case. Rehnquist's dissent had the effect of revealing the ordinarily secret vote 6-3 against hearing the case.
In the current case, lawyers for Indiana echoed Rehnquist's dissent in arguing that the proposed statehouse monument is meant to memorialize the role the commandments have played in the American legal system.
The state posed a broad question for the court that could have set the court up for a ruling on all government display of the commandments whether as an outdoor monument or inside buildings such as courthouses.
O'Bannon wanted the donated monument to replace one that was defaced by a vandal. The Indiana chapter of the American Civil Liberties Union sued, and lower federal courts blocked the installation on grounds that it promoted a religious purpose.
"To deem the Ten Commandments inappropriate for a government historical display simply because it has both religious and historical import is to insist on inaccurate and incomplete public displays of history," the state appeal said.
The original, vandalized Ten Commandments monument was one of scores donated nationwide by the Fraternal Order of the Eagles in the 1950s. Many of the recent court fights over the commandments have concerned these monuments.
The Supreme Court also declined a 1996 invitation to hear a case involving an Eagles monument near the Colorado state Capitol, meaning that monument could stay.
Federal appeals courts have reached opposite conclusions about whether the monuments are constitutional.
The case is O'Bannon v. Indiana Civil Liberties Union, 01-966.
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