 Parents of Louisiana public school children with various religious backgrounds are suing, citing the First Amendment ban on government establishment of religion. Backers of the law say the Ten Commandments are historical and are part of the foundation of U.S. law. In 1980, the Supreme Court struck down a similar Kentucky law and in 2005 tossed a law on displaying the commandments at Kentucky courthouses, though it allowed a marker at the Texas state capitol.