JUDGE BRETT M. KAVANAUGH will face the Senate Judiciary Committee on Tuesday, the first day of his confirmation hearings to replace retired Justice Anthony M. Kennedy on the Supreme Court. High-court confirmation hearings have become increasingly less illuminating over the years, with nominees finding ever more creative ways to say little. They aim to avoid the fate of Robert H. Bork, whom the Senate rejected in 1987 following a loquacious performance at his hearings. Their model is Justice Ruth Bader Ginsburg, who explained in her 1993 sessions that she could not answer certain questions because she would not want to suggest she had prejudged cases that might come before her. Yet nominees since have said far less even than Ms. Ginsburg.

Mr. Kavanaugh should break this trend. That is because the stonewalling is rendering irrelevant the most visible public opportunity to vet nominees for a lifetime appointment to the nation’s highest court. It is also because Mr. Kavanaugh has a record that compels him to speak substantively.

As with other nominees, senators must probe Mr. Kavanaugh’s judicial philosophy: Does “originalism” appeal to him, as it does to other prominent Republican-appointed judges? If so, what happens when the original meaning of a text is unclear, or controversial at the time? Does the doctrine of stare decisis constrain justices merely from overturning precedents, or also from radically narrowing previous court decisions with which justices now disagree?

Then there are questions specific to Mr. Kavanaugh’s long record in public life, including as a George W. Bush White House lawyer. The American Civil Liberties Union’s David Cole pointed out that Mr. Kavanaugh said in his 2006 appeals court confirmation hearing that he believed Mr. Bush’s insistence that the United States did not torture people. Revelations about Bush-era practices have poured out since, and President Trump promised to do worse. Does Mr. Kavanaugh still believe that U.S. actions did not rise to torture?

The justices will in coming years have to update ancient privacy doctrines for the digital age. In previous cases, Mr. Kavanagh has been less willing than his fellow judges to recognize the power of new tools such as electronic tracking devices to present novel privacy threats. He should be pressed on that point.

But the most important questions Mr. Kavanaugh must answer concern how he will negotiate his relationship with the man who appointed him, Mr. Trump. Mr. Kavanaugh wrote a 2009 Minnesota Law Review article favoring “a law exempting a President — while in office — from criminal prosecution and investigation, including from questioning by criminal prosecutors or defense counsel,” because “even the lesser burdens of a criminal investigation — including preparing for questioning by criminal investigators — are time-consuming and distracting.”

Given the ongoing investigation by special counsel Robert S. Mueller III, it is a distinct possibility that the Supreme Court will have to rule on questions relating to a criminal probe involving the president. Moreover, it is likely that Mr. Trump knew about Mr. Kavanaugh’s views when he nominated him. If Mr. Kavanaugh were to cast a decisive vote favoring Mr. Trump, it would appear as though the president put him on the court to do just that, and that Mr. Kavanaugh followed the script. Americans might question Mr. Kavanaugh’s impartiality and the decision’s legitimacy. Mr. Kavanaugh must respond with substance and detail to questions about his 2009 article. And he should explain why he would or would not recuse himself if such a case came before him.

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