Because of his senior status in the CIA, Gates was close to many figures who played significant roles in the Iran–Contra Affair and was in a position to have known of their activities. In 1984, as deputy director of CIA, Gates advocated that the U.S. initiate a bombing campaign against Nicaragua and that the U.S. do everything in its power short of direct military invasion of the country to remove the Sandinista government.[30]

Gates was an early subject of Independent Counsel's investigation, but the investigation of Gates intensified in the spring of 1991 as part of a larger inquiry into the Iran–Contra activities of CIA officials. This investigation received an additional impetus in May 1991, when President George H. W. Bush nominated Gates to be Director of Central Intelligence (DCI). The chairman and vice chairman of the United States Senate Select Committee on Intelligence (SSCI) requested, in a letter to the Independent Counsel on May 15, 1991, any information that would "significantly bear on the fitness" of Gates for the CIA post.

Gates consistently testified that he first heard on October 1, 1986, from Charles E. Allen, the national intelligence officer who was closest to the Iran initiative, that proceeds from the Iran arms sales may have been diverted to support the Contras. Other evidence proves, however, that Gates received a report on the diversion during the summer of 1986 from DDI Richard Kerr.[31] The issue was whether the Independent Counsel could prove beyond a reasonable doubt that Gates was deliberately not telling the truth when he later claimed not to have remembered any reference to the diversion before meeting with Allen in October. ...

.... Also, according to Newsweek, Gates, as deputy director of CIA, allegedly vouched for the comprehensiveness of a CIA study presented to the Senate and President Reagan alleging that the Soviet Union played a role in the 1981 shooting of Pope John Paul II. A CIA internal review later denounced the report as being skewed,[102] but that Gates did not try to influence the report's conclusions.[108]

https://en.wikipedia.org/wiki/Robert_Gates