Would Brett Kavanaugh be a check on Trump if he tried to abuse his power? We need to know. Senators and citizens deserve to know whether Kavanaugh would be a check on self-pardons or other abuses of executive power that Trump may attempt. Review all the documents.

Norman Eisen and Caroline Fredrickson | Opinion contributors

The Senate should hold all Supreme Court nominees to the same level of scrutiny. But in their rush to confirm Judge Brett Kavanaugh, Senate Republicans are abandoning rather than maintaining the standards they have insisted on in the past. History could hinge on the views Kavanaugh expressed when he worked in the George W. Bush White House, yet Republicans are no longer interested in a thorough review of his relevant documents.

So much for the “Kagan rule.” When President Barack Obama nominated Elena Kagan, then serving as solicitor general in the Justice Department, the Senate requested and received broad access to documents relating to her White House tenure as associate counsel and deputy director of the Domestic Policy Council in Bill Clinton's administration. All told, the Senate Judiciary Committee reviewed 170,000 pages of Kagan’s White House documents.

Senate Democrats want to apply the Kagan rule to Kavanaugh’s two years in the White House counsel office and his next three as staff secretary in the George W. Bush White House. Instead, the Senate Judiciary Committee's Republican majority has requested Kavanaugh's papers only for his first two years of White House service.

We deserve to know Kavanaugh's opinions

The American people should not be deprived of a searching Senate review of Kavanaugh’s work as Bush's staff secretary. Despite the title, this is no clerical job. Rather, it is a high-level White House position that at times involves advising and weighing in on critical issues under review by the president.

Kavanaugh served in this key role at a time when the Bush administration was attempting to push extreme arguments that the president is not constrained by Congress, judiciary or Senate-approved treaties in the exercise of certain executive powers. Kavanaugh’s real-time communications with his colleagues on these questions of executive power will provide a more complete picture of his perspective than will likely emerge from the careful remarks he will be making during the confirmation process.

We need to know Kavanaugh’s views on the extent of presidential power because, as we have detailed, the Supreme Court could imminently face broad claims of such authority by President Donald Trump and his legal team in defending against the inquiry by special counsel Robert Mueller into the Trump campaign's ties to Russia. The senators who will vote on the nomination and the citizens they represent deserve to know whether Kavanaugh will serve as a check on radical extensions of authority that Trump and his legal team have hinted they may attempt to execute, such as a self-pardon, a refusal to provide testimony or other abuses of executive power.

Kavanaugh’s public statements in this area only augment the imperative for in-depth review of his written records. Recently reported remarks by Kavanaugh indicate he may disagree with the Supreme Court’s unanimous 1974 decision requiring President Richard Nixon to turn over tapes to the special prosecutor in the Watergate investigation.

Other Kavanaugh statements suggest opposition to the Supreme Court’s 7-1 decision to uphold the independent counsel statute in Morrison v. Olson — and raise additional questions about his commitment to observing longstanding precedent restraining executive authority. The full set of White House records required under the Kagan rule can help illuminate Kavanaugh’s thoughts in this area.

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In arguing that the Senate should not request Kavanaugh’s staff secretary records, Senate Republican leaders have asserted they are analogous to solicitor general records the Senate considered off-limits in considering Kagan’s nomination. This comparison is inapt.

At that time, Kagan was still serving as solicitor general, and her records there concerned ongoing open matters. In contrast, Kavanaugh’s staff secretary tenure ended more than a decade ago in 2006 — and relevant materials will be subject to disclosure in the near future regardless of any nomination process under Presidential Records Act provisions requiring public release of documents 12 years after a president leaves office.

Even when it comes to Kavanaugh’s counsel role, the Republican request states that the archivist may be permitted to withhold some material “in its entirety.” The main purported basis for holdbacks — claims of executive privilege — should be viewed with deep skepticism. Senate access to sensitive executive branch materials has occurred in the review of numerous previous Supreme Court nominees irrespective of the party affiliation of the appointing president.

In the case of Kagan, neither Obama nor Clinton used executive privilege to withhold the voluminous materials produced from her White House service. That is far from the only example. The Senate obtained thousands of documents from Judge John Roberts’ service as associate counsel in the Reagan administration, including memos he authored on war powers and other critical legal issues. For Judge Robert Bork’s nomination, the Senate reviewed memos from his prior service as solicitor general, including one he authored on presidential pocket veto power.

During the William Rehnquist nomination, President Ronald Reagan initially claimed executive privilege over papers from the Office of Legal Counsel at the Justice Department, but after negotiations the Senate gained access to some of these materials.

Kavanaugh could decide Trump's fate

Beyond such precedents, the specific circumstances of this nomination demand a flexible approach to executive privilege. As discussed in a recent report one of us co-authored, executive privilege is not absolute but rather is evaluated against the public interest in disclosure.

Here, it is difficult to imagine a more compelling need for transparency. Never before has a president named as a subject in a criminal investigation chosen a justice who may decide his fate. The White House considered Kavanaugh’s views on this type of situation, according to CNN. So why shouldn’t the Senate and the American people?

Fortunately, due to Kavanaugh’s tenure in the Bush administration, his unvarnished views on presidential powers are likely documented. We know Kavanaugh’s service as an attorney in the Office of the White House Counsel included advising on separation of powers issues and monitoring certain litigation matters involving the White House. He also worked on nominating and confirming federal judicial nominees, a process that involves staff deliberation on the merits of candidates’ constitutional philosophy. One of us served in the Office of White House Counsel, and can say from firsthand experience that Kavanaugh’s candid advice on these matters is likely memorialized in memos and other records.

For these reasons, the Senate should stick with the same stare decisis approach it expects of our judicial system and apply the Kagan rule to Kavanaugh’s nomination. A thorough review of his written record for his entire White House service is essential to ensure public confidence that he — and any Supreme Court on which he sits — will meet the constitutional mandate to serve as a branch of government independent of the presidency.

Norman Eisen is chair of Citizens for Responsibility and Ethics in Washington and author of the forthcoming book "The Last Palace." Caroline Fredrickson is president of the American Constitution Society and the author of "Under the Bus: How Working Women Are Being Run Over." Follow them on Twitter: @NormEisen and @crfredrickson​​​