On October 26, 2016, on Fox Television, Rudy Giuliani joked about a big surprise coming up in the next couple of days that would turn around the election for Trump. Source Two days later, on October 28, 2016, FBI Director James Comey said that emails “pertinent” to the investigation, closed months earlier, into Hillary Clinton’s private email server had been discovered in an unrelated case on a computer belonging to Anthony Weiner, the estranged husband of Clinton campaign aide Huma Abedin. Comey’s announcement gained widespread news coverage in the final days before the election, and had a significant pro-Trump impact in polls. Source
In early 2017, former New York mayor and Donald Trump ally Rudy Giuliani, and former US attorney general Michael Mukasey joined Reza Zarrab’s defense team. In late February 2017, Giuliani and Mukasey visited Turkey to meet President Erdogan to try to negotiate a deal to secure Zarrab’s release. The available reports indicate that the negotiations did not involve the US Attorney’s office for the Southern District of New York, which is prosecuting Zarrab. Rather, the Giuliani/Mukasey team apparently negotiated on behalf of the United States, offering Zarrab’s release in exchange for “Turkey’s help furthering US interests.” Source Zarrab is reported to be cooperating with investigators looking into Michael Flynn‘s improper activities in relation to Turkey.
It appears that Giuliani had inside information about Comey’s forthcoming announcement. This information would have come from inside the FBI.