Suddaby was born in Glens Falls, New York.
He received a Bachelor of Arts degree from State University of New York at Plattsburgh in 1980 and a Juris Doctor from Syracuse University College of Law in 1985.
He was the United States attorney for the Northern District of New York from 2002 to 2008.
He was nominated to a seat vacated by Judge Lawrence E. Kahn.
He was confirmed by the United States Senate on July 22, 2008, and received commission on August 29, 2008.