Bill Cassidy studied until 1983 at the Louisiana State University in Baton Rouge medicine and worked as a doctor, where he specialized in liver diseases. At the same time he began a political career as a member of the Republican Party. Between 2006 and 2008 he was a member of the Senate of Louisiana.
In the congressional elections of 2008, Cassidy was in the sixth electoral district of Louisiana in the U.S. House of Representatives in Washington DC chosen, where he became the successor of the defeated in the election Democrats Don Cazayoux on January 3, 2009. His current term of office runs until 3 January 2011. Since he was confirmed in the elections of 2010, with 66 % of the vote, he can take another two-year term on that day. In Congress, he is a member of the Agriculture Committee, in the education and labor committee and the committee, which deals with the natural resources. He also is a member of several subcommittees.
Bill Cassidy is married to the doctor Laura Layden. The couple has three children and lives privately in Baton Rouge.