Before his retirement in 2018, McGonigal led the WikiLeaks investigation into Chelsea Manning, busted Bill Clinton’s national security advisor Sandy Berger for removing classified material from a National Archives reading room, and led the search for a Chinese mole inside the CIA. In 2016, when reports surfaced that Russia had hacked the email system of the Democratic National Committee, McGonigal was serving as chief of the cybercrimes section at FBI headquarters in Washington. In that capacity, he was one of the first officials to learn that a Trump campaign official had bragged that the Russians had dirt on Hillary Clinton, sparking the investigation known as Operation Crossfire Hurricane. Later that year, FBI Director James Comey promoted McGonigal to oversee counterintelligence operations in New York.

Late last year, according to internal court documents obtained by Insider, US attorneys secretly convened a grand jury that examined the conduct of Charles McGonigal, the former head of counterintelligence at the FBI field office in New York City. The Justice Department declined to comment on what the grand jury was investigating or whether it remained ongoing. But a witness subpoena obtained by Insider seems to indicate that the government, in part, was looking into McGonigal’s business dealings with a top aide to Oleg Deripaska, the billionaire Russian oligarch who was at the center of allegations that Russia colluded with the Trump campaign to interfere in the 2016 election.

The subpoena, issued in November, requests records relating to McGonigal and a shadowy consulting firm called Spectrum Risk Solutions. A week after the subpoena was issued, a Soviet-born immigrant named Sergey Shestakov said in a separate filing that McGonigal had helped him “facilitate” an introduction between Spectrum and Deripaska’s aide. The filing also states that McGonigal helped introduce the aide to Kobre & Kim, a New York law firm that specializes in representing clients who are being investigated on suspicion of “fraud and misconduct.” Shestakov, who has been identified on TV panels as a former Soviet foreign ministry official and former chief of staff to the Soviet ambassador to the United Nations, reported receiving $33,000 for the referrals.