A decades-old effort to get the Equal Rights Amendment into the U.S. Constitution faces another setback as Arizona Republicans again blocked a vote over whether the state should ratify it. 

Opponents say there are already sufficient laws to guarantee things like equal pay for women. But supporters argue statutory protections against gender discrimination aren’t enough.

Rep. Kelli Butler (D-Scottsdale) acknowledged the string of past defeats. But hoped things had changed.

"I guess every year we hope there's a new group of people who have talked to women in your district, maybe a new group of people who have listened to your wives or your daughters and have come to the conclusion that, yes, women should be guaranteed equal rights under the law," Butler said. 

Rep. Justin Wilmeth (R-Scottsdale) questioned the whole exercise. He pointed out that the deadline set by Congress to ratify the amendment, expired in 1982.

But Rep. Pamela Powers Hannley (D-Tucson) pointed out the U.S. House already has approved a measure to retroactively eliminate that deadline. That measure, however, faces an uncertain future in the Senate.

Deadlines aside, less clear is whether ratification by Arizona would have any legal meaning. That is because Virginia lawmakers last year took that vote, making it the necessary 38th state for approval. Powers Hannley sought to make Arizona number 39.

But five states have taken action to revoke their ratifications. And any court ruling on the validity of those actions could make action in Arizona relevant.