Louisiana becomes first US state to order every classroom to display Ten Commandments

A US state has become the first in the country to require all public schools to display the Ten Commandments in the classroom.

The Louisiana law signed by right-wing Republican governor Jeff Landry on Wednesday requires all public classrooms from nursery to university to display a poster of the Ten Commandments in “large, easily readable font”.

“If you want to respect the rule of law, you've got to start from the original lawgiver, which was Moses,” Mr Landry said, signing the law into effect.

Critics have vowed to challenge the law in court on constitutional grounds.

But supporters have said the Ten Commandments have historic, not just religious, significance, and that state funds will not be used for the posters.

The posters are slated to be accompanied by a four-paragraph "context statement" and must be in place in classrooms by the start of 2025.

The controversial law also authorises, but does not require, several other items to be displayed in public schools, including the Declaration of Independence and the Northwest Ordinance, which paved a pathway for admitting new states to the Union.

Civil rights groups vowed to challenge the law in court within hours of it being signed into effect.

The law prevents students from getting an equal education and will keep children who have different beliefs from feeling safe at school, the American Civil Liberties Union 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 controversial law comes during a new era of conservative leadership in Louisiana under Landry, who replaced two-term Democrat John Bel Edwards in January.

Similar bills have been proposed in other states including Texas, Oklahoma and Utah, but only Louisiana has thus far made it law.

In 1980, the US Supreme Court ruled that a similar Kentucky law was unconstitutional and violated a 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 rather served a plainly religious purpose.