Louisiana has become the first state to require that the Ten Commandments be displayed in every public school classroom under a bill signed into law by the Republican governor, Jeff Landry, on Wednesday. The GOP-drafted legislation mandates that a poster-sized display of the Ten Commandments in “large, easily readable font” be required in all public classrooms, from kindergarten to state-funded universities. Although the bill did not receive final approval from Landry, the time for gubernatorial action – to sign or veto the bill – has lapsed. Opponents question the law’s constitutionality, warning that lawsuits are likely to follow. Proponents say the purpose of the measure is not solely religious, but that it has historical significance. In the law’s language, the Ten Commandments are described as “foundational documents of our state and national government”. The displays, which will be 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 place in classrooms by the start of 2025. The posters would be paid for through donations. State funds will not be used to implement the mandate, based on language in the legislation. The law also “authorizes” – but does not require – the display of the Mayflower Compact, the Declaration of Independence and the Northwest Ordinance in K-12 public schools. Similar bills requiring the Ten Commandments to be displayed in classrooms have been proposed in other states including Texas, Oklahoma and Utah. However, with threats of legal battles over the constitutionality of such measures, no state besides Louisiana has had success 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 rather served a plainly religious purpose. Louisiana’s controversial law, in a state ensconced in the Bible belt, comes during a new era of conservative leadership in the state under Landry, who replaced the two-term Democratic governor John Bel Edwards in January. The GOP also has a two-thirds supermajority in the state legislature, and Republicans hold every statewide elected position, paving the way for lawmakers to push through a conservative agenda during the legislative session that concluded earlier this month.