After holding the positions of United States Attorney in the Southern District of New York and General Counsel of the Air Force, Johnson assumed the office of United States Secretary of Homeland Security.
He received his bachelor's degree from Morehouse College and his J.D. from the Columbia University Law School.
He was the first African American to become a partner at New York's Paul, Weiss, Rifkind, Wharton & Garrison law firm.
His marriage to his childhood neighbor, Dr. Susan Maureen DiMarco, resulted in children named Natalie and Jeh, Jr.
He supported the Democratic presidential campaigns of John Kerry and Barack Obama.