Former FBI Director James Comey made a bold prediction Tuesday evening regarding the bureau's investigation into three sexual assault allegations against Supreme Court nominee Brett Kavanaugh.

During an appearance at an event in Baltimore, Comey said if given adequate breadth the FBI would come up with surprising discoveries.

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“It can be done if they’re allowed to do their job,” he said, according to the Baltimore Sun. “They’ll learn more from voluntary interviews than you might expect.”

The Washington Post reported Tuesday evening that the FBI expanded its inquiry, which has a Friday deadline, beyond its initial four-person target range to include one of Kavanaugh's Georgetown Preparatory School classmates, Tim Gaudette.

Among the prior four witnesses sought by the FBI was Mark Judge, a friend and another former high school classmate of Kavanaugh's, whom one of the judge's accusers, Christine Blasey Ford, claims was in the room when she says Kavanaugh forced himself on her at a 1980s Maryland house party. The FBI completed it's interview with Judge, who, like Kavanaugh, has denied the incident occurred, earlier in the day Tuesday, according to his lawyer.

The FBI also spoke with Ford's high school friend Leland Keyser and P.J. Smyth, both of whom were identified as party guests, and Deborah Ramirez, a woman who accuses Kavanaugh of sexually assaulting her at a college party. Kavanaugh denies this allegation too, as well as the misconduct accusations made by Michael Avenatti's client Julie Swetnick.

Comey wrote an op-ed in the New York Times over the weekend expressing his faith in the FBI being able to uncover the truth. "It is better to give professionals seven days to find facts than have no professional investigation at all," Comey wrote. "Agents can just do their work. Find facts. Speak truth to power."

He also wrote Kavanaugh's "obvious lies" about his high school yearbook hint at "bigger lies" that may be uncovered, and while he acknowledged the FBI won't reach any conclusions, "their granular factual presentation will spotlight the areas of conflict and allow decision makers to reach their own conclusions."

The full Senate is expected to vote on Kavanaugh's nomination after the FBI completes its investigation.