of the
Atomic Energy Commission as subject (
person of interest) Ladd worked at his father's office initially, then helped run subway cars between
US Capitol office buildings. On November 5, 1925, having finished law school, Ladd joined the FBI as an agent. His first assignment was in
Butte, Montana, followed by
New Orleans, Louisiana. In 1931, he became a special agent, assigned to St. Louis, Missouri; St. Paul, Minnesota; Chicago, Illinois; and Washington, DC, field offices. In 1939, Ladd became assistant director of the FBI's Technical Laboratory, AKA Identification Division and Laboratory. In 1941, Ladd became head of the Security Division, which in 1942 became the FBI's Domestic Intelligence Division (in the 21st Century known as "
counterintelligence"). In this role, Ladd led investigations into Nazis (e.g.,
Operation Pastorius) during World War II and into Communists during WWII and the early
Cold War including major cases like the
Amerasia affair, {{cite book On May 5, 1949, Hoover appointed Ladd to the Number 3 position of Assistant to the Director, succeeding
Edward Allen Tamm, as second only to
Clyde Tolson. As Hoover's "assistant," Ladd's role was "supervision of all the FBI's investigative activities in both criminal and subversive fields." In 1954, Ladd retired from the FBI. In 1960, Ladd ran for Congress in the district for
Sanford, Florida, the town where he was living. ==Personal life and death==