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.