The three states that most recently ratified the Equal Rights Amendment are going to court to demand it be recognized as the 28th Amendment to the U.S. Constitution.

The state attorneys general for Virginia, Illinois and Nevada filed the complaint in the U.S. District Court for the District of Columbia on Thursday, asking a judge to order David Ferriero, the archivist of the United States, to recognize the amendment's ratification and have it added to the Constitution.

"After generations of effort, the women of this country are entitled to their rightful place in the Constitution. This court should compel the archivist to carry out his statutory duty of recognizing the complete and final adoption of the Equal Rights Amendment," the lawsuit reads.

Congress passed the ERA in 1972, but included a measure requiring it be ratified by the necessary three-fourths of states by 1982. Some constitutional experts have argued that deadline cannot hold up in court, as the Constitution itself does not include a timeline for ratification.

State legislatures have continued to take action on the amendment; Nevada ratified it in 2017, Illinois in 2018 and Virginia earlier this month. However, five states have also withdrawn or rescinded their ratification.

The Justice Department's Office of Legal Counsel recently published an opinion finding that the timeline for ratifying and adopting the ERA has run out, a guideline the archivist is likely to follow.

Rep. Jackie Speier, D-Nevada, and Sen. Ben Cardin, D-Maryland, have introduced legislation that would remove the time constraint from the ERA's language. Oversight and Reform Committee Chairwoman Carolyn Maloney, D-New York, said last year that she introduced a new version of the ERA that supporters may pursue if the other effort fails, but advocates acknowledge that it could be difficult to pass through Congress.

Read the lawsuit: