In a pitch to lawmakers, a leading liberal constitutional law scholar praised U.S. Supreme Court nominee Brett Kavanaugh as the “best candidate on the horizon,” and defended the prospective justice’s decision to avoid promising recusals in future cases involving President Donald Trump.

Yale Law professor Akhil Amar urged members of the Senate Judiciary Committee on Friday  to confirm his former law student, nearly two months after penning an op-ed that described Trump’s choice of Kavanaugh as “his classiest move.” Amar described Kavanaugh as someone whose qualifications cannot be knocked.

“Kavanaugh has studied the Constitution with more care, consistency, range, scholarliness, and thoughtfulness than any other sitting Republican federal judge under age 60,” said Amar, who voted for Hillary Clinton in 2016. Amar added, “He is the best choice from the long list of 25 potential nominees publicly circulated by President Trump.”

Amar also backed Kavanaugh after the nominee took heat for declining to promise he’d step aside from any future case involving Trump and the special counsel probe. Senate Democrats have sought assurances from Kavanaugh that he would recuse. During two days of questioning, Kavanaugh avoided commenting on future cases or recusal matters, saying he wanted to protect the “independence of the judiciary.”

“Judicial nominees should not make substantive promises about how they will rule on specific legal issues,” Amar said, “nor should they make recusal promises that closely approximate substantive promises.”

Sen. Sheldon Whitehouse, D-Rhode Island, later pressed Amar on that thought. Since Kavanaugh was nominated by a president who is involved in an ongoing criminal investigation, and was named in open court as directing criminal activity, Whitehouse asserted, “it is fair to say, is it not, that the question of recusal is a very live and legitimate issue?”

Amar agreed, noting back to United States v. Nixon in 1974 when Justice William Rehnquist, once an assistant attorney general in John Mitchell’s Justice Department, recused himself. Three other justices declined to recuse.

“My thought is that that has to be decided when the case arises and there should never be a promise of any sort to any nominator or to this body in the confirmation process about how you’ll vote or even how you’ll recuse,” Amar said. “You decide that when the case comes before you, and Rehnquist decided one way and three other justices appointed by President Nixon had decided the other way.”

Amar’s praise of Kavanaugh came after the professor’s New York Times op-ed in July, titled “A Liberal’s Case for Brett Kavanaugh,” described Trump’s nomination of Kavanaugh as the president’s “finest hour, his classiest move.” That column drew consternation from some liberals and “a lot of hate mail,” Amar told the National Law Journal.

In his testimony to lawmakers Friday, Amar sought to persuade Democrats to look more optimistically at Kavanaugh’s record, describing Kavanaugh as an originalist who would “very seriously take the vision” of the Reconstruction and the women’s suffrage generations.

And on “vital issues” such as voting rights and congressional power to enforce the Reconstruction Amendments, Amar said Kavanaugh’s “constitutional views may well be better for liberals than were Justice Kennedy’s.”

Amar also urged Democrats to consider Kavanaugh against the other nominees on Trump’s short list.

“Don’t be mad. Be smart, and be careful what you wish for,” he warned, reminding Democrats they control neither the White House nor Senate. “If you torpedo Kavanaugh, you’ll likely end up with someone worse—less brilliant, less constitutionally knowledgeable, less studious, less open-minded, less good for America.”

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