Gov. Spencer Cox, a Republican, signed H.B. 72 after carefully considering whether to sign or veto it.

Cox told reporters during a recent press conference that the proliferation of phones has made it difficult for parents to police what their children are watching.

"I do think that pornography is a problem with it, especially with younger and younger people and what it does to their brains when they don't have a real ability to understand and to make those choices. So really, we want to empower parents," he said, adding, "If nothing else, it sends an important message, I think, to people that we need to do better there and then we'll see what other states do."

Legislators amended the bill to put off its activation until five other states approve similar laws.

The American Civil Liberties Union (ACLU) of Utah said the constitutionality of the bill was not adequately considered and that it will likely be argued in court.