Louisiana has become the first state in the US to require the Ten Commandments be displayed in every public school classroom.

It is the latest move from a Republican-dominated legislature pushing a conservative agenda under a new governor.

Republican Governor Jeff Landry signed the law into legislation on Wednesday requiring a poster-sized display of the Ten Commandments in “large, easily readable font” in all public classrooms, from kindergarten to state-funded universities.

“If you want to respect the rule of law, you’ve got to start from the original lawgiver, which was Moses” Governor Landry said.

APTOPIX Ten Commandments Law Louisiana
Jeff Landry signs bills related to his education plan on Wednesday (Brad Bowie/The Times-Picayune/The New Orleans Advocate via AP)

Opponents questioned the law’s constitutionality and vowed to challenge it in court. Proponents said the measure is not solely religious, but has historical significance.

The posters, paired with a four-paragraph “context statement” describing how the Ten Commandments “were a prominent part of American public education for almost three centuries” must be in classrooms by the start of 2025.

State funds will not be used to implement the mandate which would be paid for through donations.

The law also “authorises”, but does not require the display of other items in K-12 public schools, including The Mayflower Compact -which was signed by pilgrims aboard the Mayflower in 1620 and is often referred to as America’s First Constitution – the Declaration of Independence and the Northwest Ordinance, which established a government in the Northwest Territory and created a pathway for admitting new states to the Union.

Civil rights groups and organisations that want to keep religion out of government promised to file a lawsuit challenging it.

The American Civil Liberties Union, Americans United for Separation of Church and State and the Freedom from Religion Foundation said in a joint statement on Wednesday that the law prevents students from getting an equal education and will keep children who have different beliefs from feeling safe at school.

“Even among those who may believe in some version of the Ten Commandments, the particular text they adhere to can differ by religious denomination or tradition. The government should not be taking sides in this theological debate,” the groups said.

 In the language of the law, the Ten Commandments are “foundational documents of our state and national government.”– (AP Photo/Stephen B. Morton, File)

The controversial law comes during a new era of conservative leadership in Louisiana under Governor Landry, who replaced two-term Democratic Governor John Bel Edwards in January.

The Republican Party holds a supermajority in the legislature and every statewide elected position, enabling lawmakers to pursue a conservative agenda.

Similar bills requiring the Ten Commandments to be displayed in classrooms have been proposed in other states, including Texas, Oklahoma, and Utah. With threats of legal battles over the constitutionality of such measures, no state besides Louisiana has succeeded in making the bills law.

Legal battles over the display of the Ten Commandments in classrooms are not new.

In 1980, the US Supreme Court ruled that a similar Kentucky law was unconstitutional and violated the establishment clause of the US Constitution, which says Congress can “make no law respecting an establishment of religion.”

The high court found that the law had no secular purpose but instead served a religious purpose.