The American Civil Liberties Union (ACLU) and the New Mexico Attorney General’s office wrapped up their arguments Sept. 21 over the validity of a New Mexico law that seeks to prevent children from viewing “harmful material” online.

In June, Federal District Court Judge C. LeRoy Hansen issued a temporary injunction against the state law, which is similar to the federal Communications Decency Act of 1996 (CDA), after hearing arguments that it would have a “chilling effect” on internet speech.

The state appealed the lower court ruling, asking the 10th Circuit Court of Appeals to reinstate the legislation, which was signed into law by New Mexico Gov. Gary Johnson in March. Observers expected the appeals court to render its decision sometime in the next six months.

Most of the CDA’s provisions were declared unconstitutional by the U.S. Supreme Court following the law’s passage. But in addition to First Amendment arguments, the ACLU is challenging the New Mexico law on the grounds that it violates the Commerce Clause of the U.S. Constitution.

“New Mexico can’t pass a law that affects people in other states,” ACLU attorney Ann Beeson said.

Experts expect the ACLU to use this case as a stepping stone on the way to an all-out battle set to commence in November over the federal Child Online Protection Act (COPA), which has been dubbed CDA II by some of its opponents.