Prior to assuming the role of U.S. Attorney, he served as an Assistant United States Attorney for the District of Maine.

Frank previously served as an Assistant United States Attorney in the District of Columbia and as a trial attorney in the torts branch of the civil division in the United States Department of Justice.

[1] He has prosecuted a number of high-profile criminal cases in Maine.

[3] He was confirmed by the United States Senate on October 3, 2017.

On February 8, 2021, he along with 55 other Trump-era attorneys were asked to resign.