Hoover expanded the FBI into a larger crime-fighting agency and instituted a number of modernizations to policing technology, such as a centralized fingerprint file and forensic laboratories.

[21] Hoover soon became the head of the Division's Alien Enemy Bureau, authorized by President Woodrow Wilson at the beginning of World War I to arrest and jail allegedly disloyal foreigners without trial.

Targets during this period included Marcus Garvey;[25] Rose Pastor Stokes and Cyril Briggs;[26] Emma Goldman and Alexander Berkman;[27] and future Supreme Court justice Felix Frankfurter, who, Hoover maintained, was "the most dangerous man in the United States.

Many of these criminals frequently made newspaper headlines across the United States, particularly John Dillinger, who became famous for leaping over bank cages, and repeatedly escaping from jails and police traps.

A raid on a summer lodge in Manitowish Waters, Wisconsin, called "Little Bohemia", left a Bureau agent and a civilian bystander dead and others wounded; all the gangsters escaped.

[50][page needed] Other writers believe Costello corrupted Hoover by providing him with horseracing tips, passed through a mutual friend, gossip columnist Walter Winchell.

In fact, Cosa Nostra's control of the Syndicate's many branches operating criminal activities throughout North America prevailed and was heavily reported in popular newspapers and magazines.

[58] In the Quirin affair, during World War II, German U-boats set two small groups of Nazi agents ashore in Florida and on Long Island to cause acts of sabotage within the country.

[59] During this time period President Franklin D. Roosevelt, out of concern over Nazi agents in the United States, gave "qualified permission" to wiretap persons "suspected ... [of] subversive activities".

[61] In the late 1930s, President Franklin D. Roosevelt gave Hoover the task to investigate both foreign espionage in the United States and the activities of domestic communists and fascists.

In 1950, at the outbreak of the Korean War, Hoover submitted a plan to President Truman to suspend the writ of habeas corpus and detain 12,000 Americans suspected of disloyalty.

[65] In 1956, Hoover was becoming increasingly frustrated by U.S. Supreme Court decisions that limited the Justice Department's ability to prosecute people for their political opinions, most notably communists.

[68] COINTELPRO's methods included infiltration, burglaries, setting up illegal wiretaps, planting forged documents, and spreading false rumors about key members of target organizations.

[70][71] This program remained in place until it was exposed to the public in 1971, after the burglary by a group of eight activists of many internal documents from an office in Media, Pennsylvania, whereupon COINTELPRO became the cause of some of the harshest criticism of Hoover and the FBI.

According to Laurence Silberman, appointed Deputy Attorney General in early 1974, FBI Director Clarence M. Kelley thought such files either did not exist or had been destroyed.

During a national speaking tour, Howard had criticized the FBI's failure to investigate thoroughly the racially motivated murders of George W. Lee, Lamar Smith, and Emmett Till.

[78][77] King's aide Andrew Young claimed in a 2013 interview with the Academy of Achievement that the main source of tension between the SCLC and FBI was the government agency's lack of black agents, and that both parties were willing to co-operate with each other by the time the Selma to Montgomery marches had taken place.

[80][81] The FBI spread rumors that Liuzzo was a member of the Communist Party and had abandoned her children to have sexual relationships with African Americans involved in the civil rights movement.

[86] Hoover also personally ordered to cease the Federal inquiry into the 1963 16th Street Baptist Church bombing by members of the Ku Klux Klan that killed four girls.

[95] Similarly, Presidents Harry Truman and John F. Kennedy considered dismissing Hoover as FBI Director, but ultimately concluded that the political cost of doing so would be too great.

Biographer Kenneth D. Ackerman summarizes Hoover's legacy thus: For better or worse, he built the FBI into a modern, national organization stressing professionalism and scientific crime-fighting.

Martin also says that such social conservatism was not only religious but also racial in nature, as Hoover aimed to maintain the ethnic dynamics of his days, including the legal superiority of the White Americans over the minorities.

He gave many dogs to notable people, such as Presidents Herbert Hoover (not closely related) and Lyndon B. Johnson, and buried seven canine pets, including a Cairn Terrier named Spee De Bozo, at Aspen Hill Memorial Park, in Silver Spring, Maryland.

"[133] Anthony Summers, who wrote Official and Confidential: The Secret Life of J. Edgar Hoover (1993), stated that there was no ambiguity about the FBI director's sexual proclivities and described him as "bisexual with failed heterosexuality.

In his book, Official and Confidential: The Secret Life of J. Edgar Hoover, biographer Anthony Summers cites multiple primary sources regarding Lansky's use of blackmail to gain influence with politicians, policemen and judges.

One stage for Lansky's acquisition of blackmail materials was orgies held by late attorney and Hoover protégé, Roy Cohn, and liquor magnate, Lewis Rosenstiel, who had lasting ties with the Mafia from his bootleg operations during Prohibition.

According to Summers, organized crime figures Meyer Lansky and Frank Costello obtained photos of Hoover having sex with Tolson and used them to ensure that the FBI did not target their illegal activities.

"[147] Skeptics of the cross-dressing story point to Susan Rosenstiel's lack of credibility (she pleaded guilty to attempted perjury in a 1971 case and later served time in a New York City jail).

In the words of author Thomas Doherty, "For American popular culture, the image of the zaftig FBI director as a Christine Jorgensen wanna-be was too delicious not to savor.

He views Rosenstiel as a liar who was paid for her story, whose "description of Hoover in drag engaging in sex with young blond boys in leather while desecrating the Bible is clearly a homophobic fantasy."