Supreme Court nominee Brett Kavanaugh on Wednesday said sitting U.S. presidents are subject to all laws, adding a “good judge” is one that is not “swayed by political or public pressure.”

Notably, he hailed a high court decision that forced then-President Richard Nixon to hand over information to federal investigators.

Standing firm in the face of political pressure “takes some backbone, takes some fortitude,” he said, hailing Supreme Court justices in cases like Brown vs. Board of Education that ended state-sponsored school segregation and U.S. vs. Nixon that required the president to respond to a subpoena.

[Trump Tweet-Slams Democrats Before Kavanaugh Finishes Opening Remarks]

Democratic senators are concerned Donald Trump’s second Supreme Court nominee might be too conciliatory toward the 45th president — especially since he has written that a sitting president is immune to criminal indictments.

Kavanaugh hailed those “great moments” in the court’s history, saying justices from various political stripes came together “great moments of unanimity and independence.”

[Kavanaugh Hearing Erupts in Chaos as Dems Demand Documents]

Judiciary Chairman Charles E. Grassley, R-Iowa, went right at the matter in his opening questions, asking the nominee to explain his views on presidency and the law.

“No one is above the law in our Constitutional system,” Kavanaugh said, adding the country’s founders set up the executive branch to be subject to the law.

“We don’t make decisions based on who they are, or their policy preferences, or the moment,” he said, saying he makes decisions based on the law.

“I’m a pro-law judge and I’ve ruled for parties based on whether they have the law on their side,” he told Grassley. “If you walk into my courtroom and you have the best legal arguments, you will win.”

Kavanaugh said he is a believer in legal precedent, saying it comes from Article 3 of the Constitution and is “rooted” in that document. “People need to know in this country that the judges are independent,” he said, saying his personal views “are not relevant to how I decide cases” whereas he “pay[s] heed to the rules of precedent.”

“Precedent is the foundation of our system, it’s part of the stability” of the legal system, he said.

Ranking member Dianne Feinstein, D-Calif., pressed the 12-year veteran of the U.S. Court of Appeals for the District of Columbia Circuit on his stance on semi-automatic weapons.

He explained one ruling in which he contends he followed a high court precedent that semi-automatic weapons are dangerous but not unusual; deciding a firearm can be both would allow them to be banned, like automatic machine guns. Feinstein took umbrage with his contention that the number of semi-automatic weapons — rather than simply how often they are used — is how he came to conclude they are not unusual.

Watch: Schumer Forces Senate to Adjourn to Protest Kavanaugh Hearing

When pressed by Feinstein, the nominee sidestepped a question on whether a sitting president has to answer a subpoena, calling it a “hypothetical” that would cause him to reveal a ruling on a potential future case. He said all sitting Supreme Court justices since Ruth Bader Ginsburg have declined to answer such questions.

Under questioning from GOP Sen. Orrin Hatch of Utah, Kavanaugh said it is not proper for judges to “re-write” laws passed by Congress.

Sen. Patrick Leahy, D-Vt., tried time and again to get Kavanaugh to express any semblance of knowledge about documents a Senate GOP staffer stole from Democratic offices, including his, in 2002. Each time, Kavanaugh denied any knowledge of the theft or that the George W. Bush White House received information that raised red flags about questions Democratic senators wanted to ask judicial nominees, and said it is standard practice for any White House to work with congressional aides to prepare for confirmation hearings.

“So far, I hear no such evidence. What happened to Leahy & Sen Jud Comte was horrible and criminal. But I don’t so far see anything whatsoever saying J.Kav knew about it,” Neal Katyal, acting Solicitor General from May 2010 until June 2011 under President Barack Obama, tweeted during the back-and-forth.

Democrats tried to corner Kavanaugh, who held several positions in the George W. Bush White House, on whether he was part of its post-9/11 terrorist detention and interrogation program. Each time, the nominee told senators he was not involved in crafting the rules for the initiative but would have fielded documents on it “prepared by others” and taken them to Bush. “I was not read into the program,” he contended several times.

Trump told reporters at the White House Wednesday afternoon that he had tuned into some of the Judiciary Committee’s session.

“I am happy with the Kavanaugh hearings,” he said. “I watched today for a little while. I saw some incredible answers to very complex questions. He’s an outstanding intellect. He’s an outstanding judge. He was born for the position.”

Kavanaugh told Sen. Amy Klobuchar that whether certain actions by a president would be an impeachable offense is up to Congress to decide, not a high court justice.

Asked by Klobuchar about campaign contributions, Kavanaugh noted he has twice voted to uphold limitations. One ruling, he said, went against the Republican National Committee. In other appellate court cases, he ruled to topple limits because “they were too low.”

Sometimes-Trump critic Sen. Ben Sasse, R-Neb., said he would not be planning to vote for Kavanaugh if he had concluded the nominee believes a president is immune to criminal charges or adhering to the legal system. The judge replied by again saying no one is above the law, though he stated whether a criminal process could begin while a president is still in office remains an unsettled question.

Watch: 4 Things Democrats Will Grill Kavanaugh About on Day 2

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