Mark A. Klaassen
Mark A. Klaassen was sworn in as United States Attorney for the District of Wyoming on November 21, 2017.
Mr. Klaassen was nominated by President Donald Trump on July 21, 2017, and was confirmed by the Senate on November 9, 2017. As U.S. Attorney, Mr. Klaassen is the chief federal law enforcement official in the District of Wyoming. The office is responsible for prosecuting federal crimes occurring in the district, including crimes related to public corruption, child exploitation, firearms, and narcotics. The office also defends the United States in civil cases and collects debts owed to the United States.
Prior to his nomination, Klaassen served for almost nine years as an Assistant United States Attorney for the District of Wyoming, where he worked on affirmative civil and financial litigation cases. During that time, he was also elected to the Board of Trustees for Laramie County School District Number One.
Before joining the United States Attorney’s Office, Klaassen was appointed by President George W. Bush to serve as Chief of Staff to the General Counsel for the Department of Homeland Security from 2007 to 2009. Prior to that appointment, Klaassen worked as General Counsel for the U.S. House Committee on Homeland Security from 2003 to 2007.
Klaassen began his career in Cheyenne as a law clerk for the Honorable Wade Brorby of the United States Court of Appeals for the Tenth Circuit, and later joined the law firm of Latham & Watkins LLP. He received his B.S. in Finance, summa cum laude, from Oral Roberts University and his J.D., magna cum laude, from Notre Dame Law School.