The Editorial Board, USA TODAY

During this week's Senate hearings on the Supreme Court nomination of federal appeals Judge Brett Kavanaugh, everyone stuck to the script.

Protesters screamed and were ejected. Republicans tossed softballs at President Donald Trump’s nominee. Democrats sharply cross-examined him on abortion, executive power and his view of barriers a president might erect against a criminal investigation.

And Kavanaugh, the central player, lived up to Republican Sen. Orrin Hatch’s previous description of him as the “human incarnation of a vanilla ice cream cone.”

The veteran of 12 years on the appellate bench came off as knowledgeable and unshakable, revealing nothing that would move any of the 11 committee Republicans to vote against him nor entice any of the 10 Democrats to vote for him.

What stands out most after more than 24 hours of questioning is how much of Kavanaugh’s thinking remains a deep, dark hole. Among the great unknowns:

►Precedent. At the hearing, Kavanaugh repeatedly sung the praises of sticking to precedent, which he said ensures stability and predictability in the law. However, in a 2016 law review article, he wrote that while lower court judges must adhere to Supreme Court decisions, the Supreme Court has “some flexibility, as it must” in adhering to its own past decisions. It remains unclear, in Kavanaugh's estimation, when flexibility should kick in.

►Abortion. Would Kavanaugh vote to overturn Roe v. Wade, the 1973 decision that legalized abortion? Trump vowed to name justices who would. Under grilling by Democrats, Kavanaugh allowed that Roe is a precedent that "has been reaffirmed many times.” But he did not say it was decided correctly — which would have been a more positive affirmation.

In a 2003 email from his time in the Bush White House, revealed Thursday by The New York Times, Kavanaugh wrote, “I am not sure that all legal scholars refer to Roe as the settled law of the land.” Last October, he asserted in a dissent that “the government has permissible interests in favoring fetal life." This all adds up to a question mark on where he stands on one of today's most contentious issues.

►Documents. Democrats declared war over nearly 200,000 documents from Kavanaugh’s five years in the George W. Bush White House that have been marked “committee confidential”— meaning senators could see them but not reveal them publicly. On Thursday, two senators released a few pages of that cache. While not a bombshell, one offered a glimpse of Kavanaugh’s thinking on a Transportation Department program he called “a naked racial set-aside.”

More than anything, the release raised the question of why such a huge swath of Kavanaugh's paper trail has been withheld. The documents provide insights that Americans have every right to see about someone seeking a lifetime seat on the highest court in the land.

►Presidential immunity. At the hearing, Kavanaugh has been eager to distance himself from his 1999 assertion that U.S. v. Nixon — the unanimous Supreme Court ruling ordering President Richard Nixon to turn over tapes of White House conversations to an independent counsel — may have been “wrongly decided.” The tapes ultimately led to Nixon’s resignation. Kavanaugh repeatedly called it one of the "four greatest moments in Supreme Court history," but he added pointedly “that the subpoena for the information, the tapes, was enforceable in that context.”

Does that suggest a different view if Trump faced a subpoena in special counsel Robert Mueller's investigation? And what about Kavanaugh’s expansive views of executive authority and his 2009 law review article suggesting that Congress consider passing a law exempting presidents from facing personal lawsuits, prosecutions or even criminal investigations while in office?

Kavanaugh told senators those “were ideas for Congress to consider. … not my constitutional views.” Again, enough contradictions to obscure Kavanaugh's thinking even as a report by Mueller looms.

The whole idea of Senate hearings into judicial nominees, particularly those chosen for lifetime appointments on the nation's highest court, is to open their records, their qualifications and their judicial philosophy to public scrutiny.

But partisan politics, the habit of nominees to reveal as little as possible and the increasing politicization of the Supreme Court have turned what should be a great rite of democracy into exercises in futility.

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