Last year, before he became a supreme court nominee, Brett Kavanaugh hired the son of a close friend to serve as his clerk, even though the clerk had not earned a spot on the Yale Law Journal, as almost all Kavanaugh’s previous Yale clerks had.

The decision to hire Clayton Kozinski, son of the now disgraced judge Alex Kozinski, smacked of the kind of cronyism that is rife in federal courts. It was especially common for Kavanaugh, who not only had a reputation for hiring “model-like” female clerks, but also the children of powerful friends and allies.

The move also marked the culmination of a decades-long professional and personal relationship with Alex Kozinski – the first high-profile judge to be forced to resign in the #MeToo era – that had helped launch Kavanaugh’s career.

Attention is now centered on allegations of sexual assault against Kavanaugh, which he has strenuously denied under oath and are the subject of a new FBI investigation.

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But serious concerns about whether Kavanaugh lied under oath have also been raised – publicly and privately – on a topic that has received far less attention in the national spotlight: his insistence that he was shocked when he discovered last year that Kozinski, his mentor and friend, sexually harassed more than a dozen clerks in decades on the bench.

In sworn testimony, Kavanaugh said the revelation – which became public following an exposé in the Washington Post last year that eventually led to Kozinski’s resignation as chief judge of the ninth circuit court of appeals – had been a shocking “gut punch” and deeply disappointing.

Kavanaugh had his own authority, also as a judge, to do something, and he didn’t Former clerk to another judge

People who knew Kozinski have privately – and in some cases, publicly – challenged that statement, saying Kozinski’s abusive behaviour, which ranged from kissing clerks to showing them pornography at work to making sexist remarks, was known throughout the judiciary. There were also public signs of his inappropriate use of pornography at work.

Individuals who knew Kozinski and spoke to the Guardian on the condition that their names be withheld, for fear of retribution, described Kavanaugh’s testimony as “ridiculous” and “unbelievable”.

“People were warned about Kozinski, that he was sexually gross,” said one former law clerk who served for a judge who worked in close proximity to Kozinski. “But they traded in their life for a year so that they could get a Kennedy clerkship, and then you are set for life.”

He was referring to Kozinski’s role as a “feeder” judge who vetted clerks for supreme court justice Anthony Kennedy. “Eventually, Kavanaugh had his own authority, also as a judge, to do something, and he didn’t.”

Kavanaugh’s relationship with Kozinski began in the early 1990s. As a top student at Yale law school, Kavanaugh had competed with another classmate, Alex Azar – a friend who is now secretary of health in the Trump administration – for a Kozinski clerkship.

Azar got the job with Kozinski but left it six weeks later, a decision that was described by one fellow classmate at the time as “jaw-dropping” because the clerkship was seen as a clear path to a clerkship at the supreme court. Azar has never explained publicly why he left, but people close to him at the time told the Guardian they believe that Azar, a social conservative, may have felt uncomfortable with Kozinski’s behaviour, which it later emerged included looking at copious amounts of pornography in the office.

Azar’s social circle at the time included Kavanaugh, who he has called a good friend, and Christopher Wray, now director of the FBI, also a graduate of Yale Law School.

Facebook Twitter Pinterest Alex Azar is now Donald Trump’s health secretary. Photograph: Mary Altaffer/AP

Azar declined to comment to specific questions about whether he discussed his reason for leaving Kozinski’s office with either Kavanaugh or Wray.

Any disclosure of concerns about Kozinski would have directly contradicted Kavanaugh’s sworn testimony. It would also raise questions about whether Wray has any personal knowledge about the situation, and whether Kavanaugh’s testimony about his lack of awareness of Kozinski’s alleged abusive behavior was truthful.

When Kozinski called Yale to seek a new clerk to fill the role Azar had vacated, Kavanaugh got the job.

The FBI declined to comment.

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In an emailed statement, a spokeswoman for the Department of Health and Human Services said: “The secretary [Azar] had no knowledge of any circumstances that led to the later alleged sexual misconduct by Judge Kozinski, nor did he witness any sexually inappropriate behavior during his clerkship.”

‘Never having to say you’re sorry’

About a decade later, Kavanaugh would have become aware of another incident involving the judge. In 2001, Kozinski and another judge purposely sabotaged an internet security system that had been put in place after a review of the court’s use of bandwidth found that judges were downloading pornography at work. In one sample size, it amounted to nearly 4% of sites visited and in some cases involved imagery of sexual abuse.

According to a 2007 letter written by the former head of the administrative office of the courts to judge Ralph Winter, who chaired a judicial conduct committee, when Kozinski “sabotaged” the computer system he opened the door for hackers to break into US court records. He did so, Ralph Mecham wrote in his letter recounting the events, in order to defend “the unfettered ability of all judges and court employees to illegally download pornography and view it in federal courts”.

In 2008, the Los Angeles Times reported that Kozinski regularly distributed raunchy and offensive jokes to former clerks, judges and journalists, among others, in an infamous email list. Kavanaugh has testified under oath that he cannot remember if he had ever received such emails.

In 2015, Kavanaugh appeared with Kozinski on a panel to discuss clerkships. At the event, which was recorded on video, Kozinski jokingly teased that “being a judge means never having to say you’re sorry”, eliciting laughter from the male judges on the panel.

On the panel, Kavanaugh also endorsed a paper Kozinski had written on the hiring process for clerks. The paper, titled Confessions of a Bad Apple, purposely used crude sexual imagery, such as use of the acronym “Limp”, which one former Kozinski clerk said was a “strained acronym that was meant to be funny and [refer to] limp penises”. In the paper he also referred to male clerks as “hot dogs”.

“Kozinski was saying them [sexual things] so much that [he] put them in articles and opinions,” the former clerk told the Guardian.

It simply doesn’t ring true … that … Kavanaugh would be in the dark about allegations of impropriety related to Kozinski Laura Gomez, LA Times

In 2017, when the Washington Post exposed Kozinski’s alleged sexual misconduct, accounts included Kozinski showing a female clerk pornographic images and asking her if it turned her on. Kozinski resigned and apologised but said he had been misunderstood. He was never formally subject to a complete judicial investigation following his resignation.

Last week, Laura Gomez, a UCLA law professor and former clerk, wrote in the Los Angeles Times that she doubted Kavanaugh’s truthfulness regarding sexual assault allegations by Dr Christine Blasey Ford precisely because she believed he had not been forthcoming about his knowledge of Kozinski’s harassment. Gomez met Kozinski in 1992 while she was clerking for a judge on the same appeals court as Kozinski, who she said had a “creepiness factor”. It was one year after Kavanaugh’s clerkship ended.

“It simply doesn’t ring true to me that, as he asserted during the confirmation process, Kavanaugh would be in the dark about allegations of impropriety related to Kozinski,” Gomez wrote. She added: “I can’t help connecting the dots between a boys-will-be-boys high school culture, socialization into the legal profession by a ribald mentor, and what appears to be a convenient, willful blindness to that mentor’s obvious missteps.”

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Kavanaugh testified this month that when he first learned last year of Kozinski’s alleged harassment, he called the judge, fearing for his mental health.

Last year, he hired Kozinski’s son Clayton – also a Yale Law graduate – to serve as his clerk. Of the 19 previous and forthcoming clerks Kavanaugh has hired from Yale Law School, only four, including Clayton Kozinski, have not had a spot on Yale Law Journal, a prestigious sign of academic achievement. The three others had other remarkable academic achievements, including graduating summa cum laude from Harvard, being a Rhodes Scholar, and earning two masters degrees between undergraduate and law school.

After serving Kavanaugh, Clayton Kozinski, who declined to comment to the Guardian, will go on to clerk for another high-profile judge: Justice Anthony Kennedy, whose seat Kavanaugh hopes to fill.

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