[6][7] Despite its domestic focus, the FBI also maintains a significant international footprint, operating 60 Legal Attache (LEGAT) offices and 15 sub-offices in U.S. embassies and consulates across the globe.

]Attorney General Bonaparte, using Department of Justice expense funds,[14] hired thirty-four people, including some veterans of the Secret Service,[18][19] to work for a new investigative agency.

During the "War on Crime" of the 1930s, FBI agents apprehended or killed a number of notorious criminals who committed kidnappings, bank robberies, and murders throughout the nation, including John Dillinger, "Baby Face" Nelson, Kate "Ma" Barker, Alvin "Creepy" Karpis, and George "Machine Gun" Kelly.

Earlier, through the work of Edwin Atherton, the BOI claimed to have successfully apprehended an entire army of Mexican neo-revolutionaries under the leadership of General Enrique Estrada in the mid-1920s, east of San Diego, California.

[20] After Katz v. United States (1967) overturned Olmstead, Congress passed the Omnibus Crime Control Act, allowing public authorities to tap telephones during investigations, as long as they obtained warrants beforehand.

[23] Robert Shivers, head of the Honolulu office, obtained permission from Hoover to start detaining those on the list on December 7, 1941, while bombs were still falling over Pearl Harbor.

[24][better source needed] Mass arrests and searches of homes, in most cases conducted without warrants, began a few hours after the attack, and over the next several weeks more than 5,500 Issei men were taken into FBI custody.

FBI Director Hoover opposed the subsequent mass removal and confinement of Japanese Americans authorized under Executive Order 9066, but Roosevelt prevailed.

[26] The vast majority went along with the subsequent exclusion orders, but in a handful of cases where Japanese Americans refused to obey the new military regulations, FBI agents handled their arrests.

On June 20, 1951, Hoover expanded the program by issuing a memo establishing a "uniform policy for the handling of the increasing number of reports and allegations concerning present and past employees of the United States Government who assertedly [sic] are sex deviates".

In 1956, for example, Hoover sent an open letter denouncing Dr. T. R. M. Howard, a civil rights leader, surgeon, and wealthy entrepreneur in Mississippi who had criticized FBI inaction in solving recent murders of George W. Lee, Emmett Till, and other blacks in the South.

[35] Historian Taylor Branch documents an anonymous November 1964 "suicide package" sent by the Bureau that combined a letter to the civil rights leader telling him "You are done.

[37] The files detailed the FBI's extensive COINTELPRO program, which included investigations into lives of ordinary citizens—including a black student group at a Pennsylvania military college and the daughter of Congressman Henry S. Reuss of Wisconsin.

In July 2007, U.S. District Judge Nancy Gertner in Boston found that the Bureau had helped convict the four men using false witness accounts given by mobster Joseph Barboza.

[44] In 1982, the FBI formed an elite unit[45] to help with problems that might arise at the 1984 Summer Olympics to be held in Los Angeles, particularly terrorism and major-crime.

It has settled a dispute with Richard Jewell, who was a private security guard at the venue, along with some media organizations,[49] in regard to the leaking of his name during the investigation; this had briefly led to his being wrongly suspected of the bombing.

With these developments, the FBI increased its electronic surveillance in public safety and national security investigations, adapting to the telecommunications advancements that changed the nature of such problems.

[53] On July 8, 2007, The Washington Post published excerpts from UCLA Professor Amy Zegart's book Spying Blind: The CIA, the FBI, and the Origins of 9/11.

[54] The Post reported, from Zegart's book, that government documents showed that both the CIA and the FBI had missed 23 potential chances to disrupt the terrorist attacks of September 11, 2001.

The primary reasons for the failures included: agency cultures resistant to change and new ideas; inappropriate incentives for promotion; and a lack of cooperation between the FBI, CIA, and the rest of the United States Intelligence Community.

It found the analytic model used by the FBI for interpreting results was deeply flawed, and the conclusion, that bullet fragments could be matched to a box of ammunition, was so overstated that it was misleading under the rules of evidence.

[58] An FBI informant who participated in the January 6 United States Capitol attack on democratic institutions in Washington D.C. later testified in support of the Proud boys, who were part of the plot.

In the early 1980s, Senate hearings were held to examine FBI undercover operations in the wake of the Abscam controversy, which had allegations of entrapment of elected officials.

The FBI often works in conjunction with other federal agencies, including the U.S. Coast Guard (USCG) and U.S. Customs and Border Protection (CBP) in seaport and airport security,[71] and the National Transportation Safety Board in investigating airplane crashes and other critical incidents.

In the wake of the September 11 attacks, then–Attorney General Ashcroft assigned the FBI as the designated lead organization in terrorism investigations after the creation of the U.S. Department of Homeland Security.

[84] Efforts to deploy modern computers and networking equipment were generally successful, but attempts to develop new investigation software, outsourced to Science Applications International Corporation (SAIC), were not.

In 1968, Congress passed legislation, as part of the Omnibus Crime Control and Safe Streets Act of 1968, requiring Senate confirmation of appointments of future directors.

They provide detailed data regarding the volume of crimes to include arrest, clearance (or closing a case), and law enforcement officer information.

The bureau has participated to varying degrees, which has ranged from direct involvement in the creative process of film or TV series development, to providing consultation on operations and closed cases.

The 2015 TV series Quantico, titled after the location of the Bureau's training facility, deals with probationary and special agents, not all of whom, within the show's format, may be fully reliable or even trustworthy.