He was the Chairman of the Senate Intelligence Committee between 1976 and 1979 and Chairman of the Senate Indian Affairs Committee between 1987 and 1995. He introduced the National Museum of the American Indian Act in 1984 which led to the inauguration of the National Museum of the American Indian in 2004. He was Chairman of the Senate Indian Affairs Committee between 2001 and 2003, Chairman of the Senate Commerce Committee between 2007 and 2009 and Chairman of the Senate Appropriations Committee between 2009 and 2012.