Mark J. Lesko[1] (born February 4, 1967) is an American politician and attorney who served as the acting Assistant Attorney General for the National Security Division at the United States Justice Department.

[2] Prior to that, from January 20, 2021, he was named as acting United States Attorney for the Eastern District of New York.

In addition to his career as a prosecutor in the United States Department of Justice, Lesko served as town supervisor of Brookhaven, New York.

[4] He earned a Bachelor of Arts degree in history from Yale University, where he was a quarterback on the varsity football team.

[9] Lesko defeated Mazzei by over 4000 votes and he assumed office as the supervisor of Brookhaven.