Robert Laurence Barr Jr. (born November 5, 1948) is an American attorney and politician. He served as a federal prosecutor and as a Congressman.He represented Georgia's 7th congressional district as a Republican from 1995 to 2003. Barr attained national prominence as one of the leaders of the impeachment of President Bill Clinton.Barr joined the Libertarian Party in 2006 and served on its National Committee. He was the Libertarian Party's nominee for President of the United States in the 2008 election.