When Robert Kennedy, as chief counsel of the Senate Select Committee on Improper Activities in Labor and Management, went after Teamsters leader Jimmy Hoffa in the late 1950s, he called 1,500 witnesses and generated 20,000 pages of testimony, but failed to produce a conviction. As attorney general in the Kennedy administration, he immediately established an elite "Get Hoffa" squad in the Justice Department, including tapping the IRS to add tax evasion to the arsenal against Mr. Hoffa.
IRS investigators were directed to give top priority to the tax affairs of major racketeers, who would be "subjected to the 'saturation type' investigation," according to Kennedy biographer Arthur Schlesinger Jr., including wiretapping by the IRS. This higher profile for the IRS in targeted criminal investigations raised questions at the time from legal experts who said that the purpose of tax laws was to "collect revenue, not criminals," and that audits should be random.
Moreover, the use of the IRS to target criminals soon expanded to include political enemies, as well. In November 1961, President Kennedy turned to the IRS to challenge the tax-exempt status of "right-wing extremist groups," as well as fundamentalist Christian ministers who had been critical of a Roman Catholic running for the presidency. "I don't think that the Federal Government can interfere or should interfere with the right of any individual to take any position he wants," Kennedy said a press briefing. "The only thing we should be concerned about is that it does not represent a diversion of funds which might be taxable.... I am sure the Internal Revenue system examines that."
In a move not made public at the time, the Kennedy administration established an "Ideological Organizations Audit project" within the IRS, which targeted conservative groups, such as the John Birch Society. In November, the IRS launched audits of 22 "extremist organizations," several of which lost their tax-exempt status, jeopardizing their fundraising.