James E. McMahon is an American attorney and 38th United States Attorney for the District of South Dakota.

University of South Dakota School of Law in 1977.

McMahon was nominated by President George W. Bush to be the United States Attorney for the District of South Dakota in 2002.

McMahon was sworn in as U.S. Attorney on May 12, 2002.

[1] McMahon joined in Redstone Law Firm in Sioux Falls, South Dakota, following his departure from the United States Attorney for the District of South Dakota office.