Milliken served as First Lady for fourteen years , the longest tenure of any First Lady in state history . She became known as a proponent of women 's rights and environmentalism as First Lady . In particular , Milliken became one of Michigan 's leading supporters of the Equal Rights Amendment ( ERA ) . The Equal Rights Amendment had been approved by the United States Congress in 1972 and ratified by thirty-five states , including Michigan . When the 1980 Republican National Convention , held in Detroit , removed language supporting the ERA from the convention platform , First Lady Helen Milliken boycotted the convention 's opening ceremony to attend a pro-ERA protest
1980 Republican National Convention
1980 Republican National Convention
Helen Milliken