The FBI released approximately a trove of documents from its file on detail President Donald Trump's controversial lawyer Roy Cohn.

The documents detail the agency's investigation into Cohn concerning perjury, conspiracy, obstruction of justice, and bribery, adding to Cohn's longtime reputation as a ruthless attorney who had little to no regard to ethical guidelines in his work and consulting of his associates.

While developing his cutthroat reputation, Cohn met Donald Trump after the Department of Justice brought a 1973 lawsuit against Trump and his father, Fred, for alleged violations of the Fair Housing Act after they had discriminated against black rental applicants.

Since Trump's emergence on the political stage, Cohn's ties to Trump's associates have come back under scrutiny as the president has faced numerous allegations of obstruction of justice.

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The FBI released nearly 750 pages from its file that detail investigations into President Donald Trump's controversial lawyer Roy Cohn.

The documents largely detail allegations that Cohn was involved in perjury, conspiracy, obstruction of justice, and bribery, adding to Cohn's longtime reputation as a ruthless attorney who had little to no regard to ethical guidelines in his work and consulting of his associates.

Cohn earned his fiery reputation while working as chief counsel for Sen. Joseph McCarthy in the 1950s during the senator's crusade to uncover suspected communists working undercover in the US government.

The lawyer successfully prosecuted Soviet spies Julius and Ethel Rosenberg, who were executed for stealing American atomic secrets. However, Cohn later said he had conversations with the trial judge without the presence of the Rosenberg lawyers, which represented an ethical breach by both Cohn and the judge, according to CNBC.

While developing his cutthroat reputation, Cohn met Donald Trump after the Department of Justice brought a 1973 lawsuit against Trump and his father, Fred, for alleged violations of the Fair Housing Act after they had discriminated against black rental applicants.

The Washington Post reported in 2016 that Trump met Cohn before the suit out and about in New York City and asked his advice on how to respond to discrimination allegations.

"My view is tell them to go to hell," Cohn said, according to the Post. "And fight the thing in court."

Read more: Donald Trump learned his aggressive legal style from 'the king of intimidation,' Roy Cohn

Cohn, as Trump's counsel, later filed a $100 million countersuit against the Justice Department before that suit failed and Trump settled the Justice Department's claims out of court.

The released files are scans of letters and other case documents, many of which pertain to an investigation of an alleged $50,000 bribe he paid the then-chief assistant US attorney to shield multiple stock swindlers from being indicted in 1959. After the deal was revealed, Cohn was ultimately found not guilty after a trial in 1964.

Cohn's other clients include media mogul Rupert Murdoch, the Roman Catholic Archdiocese of New York, and multiple New York mob bosses, and his controversial work never affected the place he enjoyed in high New York society among friends and associates like Nancy Reagan and Andy Warhol.

In 1986, Cohn was disbarred for ethics violations and died at the age of 59 from AIDS complications nearly two months later.

Since Trump's emergence on the political stage, Cohn's ties to Trump's associates have come back under scrutiny amid concerns of his influence on Trump's tactics to confronting issues related to the administration including obstruction of justice allegations.

One such associate is Roger Stone, a former adviser who was charged as part of special counsel Robert Mueller's Russia investigation. Stone pleaded guilty to lying to Congress, witness tampering and obstructing a congressional proceeding, and is set to stand trial in November in federal court.

A documentary that premiered this month that explores Cohn's life and influence borrowed its title from Trump's key phrase when he was facing legal troubles and would ask "Where's My Roy Cohn?"