Tuesday is the first day of Supreme Court nominee Brett Kavanaugh’s Senate confirmation hearings, a chance for senators to question President Donald J. Trump’s second nominee to the nation’s highest court.

And though its likely most senators have already made up their minds about which way they’ll vote, “a particularly disastrous or a particularly strong” performance by Kavanaugh could sway those who are still on the fence, said Dan Urman, who teaches a Northeastern course on the Supreme Court.

Here’s what to watch for during the four days of hearings.

Hot-button political issues

“Hearings are often snapshots of the most important political issues of the day,” said Urman, who holds joint appointments in the School of Public Policy and Urban Affairs and the School of Law.Watch for Democratic senators to ask Kavanaugh about his stance on issues related to affirmative action and abortion—particularly on the landmark Supreme Court case Roe v. Wade, Urman said.

“Most likely, Kavanaugh will dodge, by saying something along the lines of ‘It’s settled law’ or that he doesn’t want to comment on something that may come before the court,” Urman said.

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That Bill Clinton memo

In 1998, Kavanaugh was associate counsel in the office of independent counsel Kenneth W. Starr. Starr was in charge of the investigation into Clinton’s affair with Monica Lewinsky. Kavanaugh wrote in a memo to Starr that he was “strongly opposed” to giving Clinton any break, and proposed 10 questions for the then-president, some of which were very graphic.

“I think you’ll see Democrats use that memo to question Kavanaugh’s temperament and maturity, as well as whether his opinions then apply now to the person who nominated him,” Urman said.

Questions about Kavanaugh’s stance on the extent of executive power

This isn’t Kavanaugh’s first rodeo. In 2006, he sat through hearings for an appointment to the U.S. District Court in Washington, DC. At the time, senators questioned him about the extent of his knowledge of illegal interrogation techniques used on terror suspects. After Kavanaugh was confirmed, an investigation by The Washington Post revealed that Kavanaugh may have misled the senators in some of his answers.

“Kavanaugh could be vulnerable here if documents emerge that challenge the truthfulness of his confirmation hearings in 2006,” Urman said.

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Strong witnesses

Both Democrats and Republicans have well-rounded rosters of witnesses to call in opposition or support of Kavanaugh.Democrats are expected to call upon John Dean, the former White House counsel during the Nixon presidency, among others.

Republicans, meanwhile, have a list of witnesses that include liberal law professor Akhil Amar of Yale Law School, Republican Sen. Rob Portman of Ohio, former Secretary of State Condoleezza Rice, and liberal lawyer Lisa Blatt.

“These are people who don’t just represent establishment Republicans,” Urman said.