J. Edgar Hoover served as Director from 1924 to 1972, a combined 48 years with the BOI, DOI, and FBI. He was chiefly responsible for creating the Scientific Crime Detection Laboratory, or the FBI Laboratory, which officially opened in 1932, as part of his work to professionalize investigations by the government. Hoover was substantially involved in most major cases and projects that the FBI handled during his tenure. After Hoover's death, Congress passed legislation that limited the tenure of future FBI Directors to ten years.

Who was Director from 1924 to 1972?