Seeking confirmation to a federal judgeship after years of Democratic opposition, Brett Kavanaugh turned to one of his most powerful mentors for a boost.

Judge Alex Kozinski, of the 9th U.S. Circuit Court of Appeals in California, traveled to Washington, D.C., in 2006 to speak on behalf of Kavanaugh — “my good friend and former law clerk.” He told the Senate Judiciary Committee that Kavanaugh had the legal skills, demeanor and “sense of humanity” to be a brilliant federal judge.

Kavanaugh thanked Kozinski for advancing his career and promised to bring the same “thoughtfulness and dedication to the rule of law that Judge Kozinski has demonstrated on the bench for more than two decades.”

Twelve years later, Kavanaugh will face senators on the same committee beginning Tuesday for confirmation hearings on his nomination by President Donald Trump to the U.S. Supreme Court.

This time, he is certain to face questions about his links to Kozinski, who has since become the poster child for sexual harassment in the federal judiciary.

Kozinski abruptly retired from the appeals court last December after several female former law clerks and colleagues accused him of sexual misconduct that included touching, inappropriate sexual comments and forced viewings of pornography in his chambers.

The case has prompted the federal courts to examine how to better protect law clerks from harassment by powerful judges who can make or break their careers.

Kavanaugh is expected to be asked whether he was ever aware of any inappropriate behavior by Kozinski throughout their long association, and, if so, how he responded.

“Alex Kozinski’s relationship with Judge Kavanaugh is a legitimate area of inquiry and I plan to question Judge Kavanaugh on this topic,” Sen. Mazie K. Hirono, D-Hawaii, said in an e-mail sent by her office.

So far, no evidence has surfaced to suggest that Kavanaugh had any knowledge of Kozinski’s alleged misconduct, which included one groping accusation from 1986 and many more claims of inappropriate behavior in recent years.

White House spokeswoman Kerri Kupec said that prior to reports in The Washington Post and other media outlets last year, Kavanaugh “had never heard any allegations of sexual misconduct or sexual harassment by Judge Kozinski.”

The White House released statements from two male law clerks and one female extern who worked for Kozinski at the same time as Kavanaugh, each saying they hadn’t seen or heard of any misconduct.

They included Washington, D.C., lawyer Mark Perry, who said in an earlier Associated Press interview he was surprised by the allegations that led to Kozinski’s abrupt downfall.

“I was aware of none of that and none of that happened to my knowledge during our year,” Perry said.

Kavanaugh’s supporters have sought to paint him as a champion of women in the judiciary, noting that he has hired more female than male clerks over the last 12 years and is widely described as treating them professionally.

But some observers say Kavanaugh must have at least heard about Kozinski’s inappropriate workplace behavior, which included sending some sexually graphic and racially offensive jokes to colleagues on an e-mail “gag list.” It’s unclear whether Kavanaugh ever was aware of the judge sharing such material.

“If Judge Kavanaugh states that he never heard or observed anything that would suggest that Judge Kozinski behaved inappropriately, he is either lying or so willfully blind to judicial misconduct that he should not be appointed,” California lawyer Cyrus Sanai wrote in a recent letter to senators considering his nomination.

Sanai in 2007 discovered a personal Kozinski website that was available to the public, where the judge stored some sexually explicit photos and videos, inappropriate jokes and illegally downloaded music.

A judicial misconduct panel investigated and publicly admonished Kozinski — who characterized some of the material himself as “highly offensive,” “gross” and “demeaning” — after the site’s existence was reported by the Los Angeles Times in 2008.

Kozinski declined an AP interview request.

Kavanaugh has recalled receiving a “life-changing phone call” from Yale law school professor George Priest asking whether he was interested in an open clerkship for Kozinski at the Pasadena, Calif.-based federal courthouse in 1991.

At the time, Kozinski was considered a relatively young and brilliant conservative judge on the famously liberal appeals court.

In an interview, Priest said that he had placed another former student with Kozinski but “there were problems in the chambers” and that clerk was abruptly fired after a short time on the job. He said Kozinski blamed him for the situation and put the burden on Priest for finding a replacement quickly.

“Part of the reason I thought of Kavanaugh is it was a tough situation and you needed someone who was calm and cool and a peacemaker,” Priest recalled.

Kavanaugh, who had graduated from Yale and completed a clerkship for another federal judge, readily agreed. He has described clerking for Kozinski as a formative and intense experience in which he and other aides worked long hours for a demanding judge who had a passion for law. But his ties lasted far beyond that job.

With backing from Kozinski, Kavanaugh landed a coveted clerkship for Kozinski’s mentor Justice Anthony M. Kennedy at the Supreme Court — whom he’s now seeking to replace.

The Senate confirmed Kavanaugh to the U.S. Court of Appeals for the D.C. Circuit shortly after Kozinski gave him his “highest recommendation” in 2006, three years after George W. Bush first had nominated him to a judgeship.

There are other links between the two men.

Kavanaugh and Kozinski have together in recent years screened applicants for Kennedy clerkships. Kavanaugh hired Kozinski’s youngest son, Yale law graduate Clayton Kozinski, last year as one of his clerks.

The younger Kozinski had been in line to be a Kennedy clerk this year before the justice’s announced retirement.