By Jonathan Eberle |

Arizona House Republicans have taken legal action to defend a decades-old state law governing birth-certificate amendments after Attorney General Kris Mayes failed to confirm whether her office would appeal a recent federal ruling striking the statute down.

Speaker of the House Steve Montenegro announced Monday that the Arizona House Republican Caucus, alongside Senate President Warren Petersen, filed a motion in U.S. District Court seeking to intervene as defendants for the purpose of appealing the decision and requesting a stay pending appeal.

The move follows U.S. District Judge James Soto’s September 30 ruling, which permanently enjoined enforcement of A.R.S. § 36-337, the provision requiring proof of a “sex change operation” before the state can amend the sex marker on a birth certificate. The injunction orders the Arizona Department of Health Services to revise its regulations within 120 days and to allow amendments based on a doctor’s attestation of a “sex change.”

“Arizona’s laws are not optional,” Montenegro said in a statement. “When a federal court rewrites a statute, the Legislature has a duty to defend it. If the Attorney General won’t defend Arizona’s laws, we will. The ruling now opens the door for anyone to change the sex marker on a birth certificate with just a doctor’s note, erasing decades of statute and undermining the integrity of vital records.”

According to the motion, Republican leaders made repeated inquiries to the Attorney General’s Office beginning October 1 about whether the state would appeal. After more than two weeks without a definitive answer, House and Senate leaders moved to intervene to ensure that the state’s position would be represented before the Ninth Circuit Court of Appeals.

The legislative leaders argue that Arizona law gives them authority to defend state statutes when their constitutionality is challenged and that the Attorney General’s inaction effectively leaves the law undefended. Their filing asserts that the federal court’s ruling misapplies equal protection principles and conflicts with recent Supreme Court guidance in United States v. Skrmetti—a 2025 case addressing gender-related classifications under the Constitution.

The lawmakers also requested an immediate stay of the injunction, warning that allowing it to take effect could cause “irreparable harm” to the state by forcing the issuance of amended birth certificates that could later be invalidated if the appeal succeeds.

This legal dispute comes months after Governor Katie Hobbs vetoed HB 2438, a bill sponsored by Rep. Rachel Keshel (R-LD17) that would have barred any changes to the sex marker on birth certificates, reinforcing the same policy now at issue in court.

If granted, the intervention would allow the Arizona Legislature’s top Republicans to pursue an appeal directly to the Ninth Circuit in defense of the statute—marking a rare instance of state lawmakers stepping into a role traditionally held by the Attorney General.

Jonathan Eberle is a reporter for AZ Free News. You can send him news tips using this link.