[3][2] On July 24, 1991, Longstaff was nominated by President George H. W. Bush to a new seat on the United States District Court for the Southern District of Iowa created by 104 Stat.
He was confirmed by the United States Senate on October 31, 1991, and received his commission on November 5, 1991.
He served as chief judge from 2001 to 2006, assuming senior status on November 5, 2006.
[3] Longstaff has thus far been the only judge on the Southern District of Iowa to preside over a multidistrict litigation, related to Teflon products.
[2] His first law clerk, James E. Gritzner, also became a federal judge in the same district.