Retired U.S. Supreme Court Justice John Paul Stevens on Thursday said that high court nominee Judge Brett M. Kavanaugh, who Stevens once lauded in one of his books, does not belong on the Supreme Court.

Speaking to a crowd of retirees in Boca Raton, Stevens, 98, said Kavanaugh’s performance during a recent Senate confirmation hearing suggested that he lacks the temperament for the job.

Stevens, a lifelong Republican who is known for falling on the liberal side of several judicial rulings, praised Kavanaugh and one of his rulings on a political contribution case in the 2014 book “Six Amendments: How and Why We Should Change the Constitution.”

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“At that time, I thought (Kavanaugh) had the qualifications for the Supreme Court should he be selected,” Stevens said. “I’ve changed my views for reasons that have no relationship to his intellectual ability … I feel his performance in the hearings ultimately changed my mind.”

Commentators, Stevens said, have argued that Kavanaugh’s blistering testimony during a Sept. 27 hearing on sexual misconduct allegations demonstrated a potential for political bias should he serve on the Supreme Court.

Retired Supreme Court Justice John Paul Stevens listens to applause after his onstage interview with Palm Beach Post columnist Frank Cerabino at the Unitarian Universalist Fellowship of Boca Raton, October 4, 2018, in Boca Raton, Florida. (Greg Lovett / The Palm Beach Post)

“I think there’s merit to that criticism and I think the senators should really pay attention that,” Stevens said at a closed event hosted by retirement group, The Institute for Learning in Retirement.

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Stevens, who retired in 2010 after 35 years on the bench, stands as one of the longest-serving justices in history. Nominated by President Gerald Ford, Stevens was unanimously confirmed by the Senate.

“That’s not happening any time soon,” moderator Frank Cerabino, of The Palm Beach Post, joked about a unanimous Senate confirmation.

Stevens decried the partisan politics that have shrouded the judiciary branch in recent years.

As a justice, Stevens was one of three dissenting votes in the Bush v. Gore case that ordered Florida to end the ballot recount in the disputed presidential election between George W. Bush and Al Gore, and effectively propelled Bush to the presidency.

The audience claps for retired Supreme Court Justice John Paul Stevens during his onstage interview with Palm Beach Post columnist Frank Cerabino at the Unitarian Universalist Fellowship of Boca Raton, October 4, 2018, in Boca Raton, Florida. (Greg Lovett / The Palm Beach Post)

“Although we may never know with complete certainty the identity of the winner of this year’s presidential election, the identity of the loser is clear,” Stevens wrote in the strongly worded dissent. “It is the nation’s confidence in the judge as impartial guardian of the rule of law.”

Stevens said political leaders and the court have failed to repair the nation’s confidence in the judicial branch’s separation from the president and the Legislature.

“I think it’s worse, I regret to say it,” he said.

Since his retirement, Stevens has penned a handful of opinion pieces for the New York Times calling for dramatic liberal reform. Following the Parkland high school shooting, Stevens, a Broward County resident, called for the repeal of the Second Amendment.

While Stevens has famously sided with Democratic colleagues on topics including Guantanamo Bay prisoner rights and political contributions, he’s far from ideologically pure.

He criticized the First Amendment flag-burning case in 1989, and Thursday stood by the stance that the act of flag-burning should be illegal.

Retired Supreme Court Justice John Paul Stevens during his onstage interview with Palm Beach Post columnist Frank Cerabino at the Unitarian Universalist Fellowship of Boca Raton, October 4, 2018, in Boca Raton, Florida. (Greg Lovett / The Palm Beach Post)

When Cerabino asked Stevens why some justices, Stevens included, have sided with liberals despite being nominated by conservatives, Stevens replied that he’s never been “a political person.”

Many event attendees of opposite political affiliations said Stevens stands as a relic of a bygone era, when justices were not apparently beholden to the presidents who nominate them.

“Unfortunately, we live in an era of tunnel vision,” said Chuck Brenner, a Democrat from Jupiter. “It’s all so one-sided.”

Brenner agreed with Stevens that Kavanaugh’s “demeanor” was not befitting of a Supreme Court justice.

Stephen Udell, a Republican from Boca Raton, agreed that politics played a heavy hand in Kavanaugh’s confirmation, but disagreed on the reason why.

“The attacks on Kavanaugh are politics, but they’ve evolved to almost brutality like the Roman Colosseum,” Udell said.

Retired Supreme Court Justice John Paul Stevens during his onstage interview with Palm Beach Post columnist Frank Cerabino at the Unitarian Universalist Fellowship of Boca Raton, October 4, 2018, in Boca Raton, Florida. (Greg Lovett / The Palm Beach Post)

The U.S. Senate is scheduled to begin voting on Kavanaugh’s confirmation Friday, a day after the FBI concluded an investigation into allegations of sexual misconduct against Kavanaugh. Final votes are on Saturday. The allegations were made by California psychology professor Christine Blasey Ford and former Yale classmate Deborah Ramirez.

Ford gave an emotional testimony to the Senate Judiciary Committee in September, telling senators she was “100 percent” certain that Kavanaugh assaulted her when he was a 17-year-old student at Georgetown Preparatory School in Maryland.

Kavanaugh, President Donald Trump’s second nominee to the Supreme Court, denied the allegations, delivering a fiery defense that opened with accusations that Ford’s allegations were part of an elaborate political coup d’état. Kavanaugh called the dark allegations “revenge on behalf of the Clintons,” referring to the time he spent working for independent counsel Ken Starr during the investigation of Bill and Hillary Clinton’s finances, which led to the president’s impeachment.