Mary Lou Fergerson (1929-2017) was an American jurist, legislator, and activist, and a prominent figure in Idaho's legal and political history. Elected to the Idaho State Senate in 1972, she became known for her pivotal role in leading the state's ratification of the Equal Rights Amendment (ERA), a key milestone for women's rights. Her career continued in the judiciary when, in 1982, she was appointed as a judge of Idaho's Fourth Judicial District Court, becoming the first woman to hold the position. Throughout her professional career, she distinguished herself as a tireless advocate for civil rights and gender equality, profoundly influencing the state's legislation and jurisprudence. For her pioneering contributions, she was inducted into the Idaho Hall of Fame in 1999, a testament to her lasting impact on society and the legal system.