The case of Van Orden v. Perry was one where a citizen of Texas sued the then-governor, Rick Perry, for allowing a monument stone bearing the Ten Commandments to be placed in front of a public building. Van Orden believed that such an act was in contradiction to the Establishment Clause of the First Amendment.
The court held that Perry was justified in his actions due to the background of the U.S. being a country that is Christian in nature.
This was a precedent-setting case in the sense that the U.S. Constitution is founded on the separation of church and state; so, many believed that it would have been illegal to put any type of religious monument in front of a government building.
The court held that since the nature of the U.S. from its inception was that of a Christian country, it was not illegal to have a Christian-themed plaque or monument.