Republican Governor Jeff Landry on Wednesday signed a bill into law requiring public schools in Louisiana to display the Ten Commandments in every classroom.
The American Civil Liberties Union immediately announced legal action seeking to stop the bill, saying it violated the separation of church and state and a US Supreme Court ruling.
Law set to come into force at start of 2025
Landry signed the bill as part of a series of education reforms he said were designed to "expand faith in public schools."
"If you want to respect the rule of law, you've got to start from the original law-giver, which was Moses," he said at the signing ceremony.
The bill stipulates that the text should be in a "large, easily readable font," and installed by the start of next year.
In the Jewish and Christian traditions, the Ten Commandments are said to have been revealed to Moses by God. The story is in the Old Testament book of Exodus. The set of exhortations includes calls not to kill, steal, lie, or covet other people's possessions, as well as appeals to honor one's parents and to worship.
But the bill also stipulates that public funds should not be used to install the posters, saying the costs will instead be covered by donations.
New rules on hiring chaplains, and LGBTQ issues
Landry also approved measures authorizing the hiring of chaplains in schools, restricting teachers from mentioning sexual orientation or gender identity, and preventing schools from using a transgender student's preferred pronoun without first obtaining parental consent.
Landry said other changes would expand tutoring for underperforming students, help improve math skills, and give teachers more freedom in selecting topics to teach.
ACLU says Supreme Court precedent blocked this in Kentucky
The American Civil Liberties Union and two other groups — Americans United for Separation of Church and State, and the Freedom from Religion Foundation — said they would challenge the bill.
"Politicians have no business imposing their preferred religious doctrine on students and families in public schools," their joint statement said.
"Even among those who may believe in some version of the Ten Commandments, the particular text that they adhere to can differ by religious denomination or tradition. The government should not be taking sides in this theological debate," the groups said.
The First Amendment of the US Constitution prohibits the government from the "establishment of religion," and in 1980 the Supreme Court ruled that a Kentucky law on posting the Ten Commandments in schools was unconstitutional.
In that case, part of the court's rationale for striking down the measure was that displaying the text had no discernible secular purpose but a clear religious one.