The White House has given the FBI until Friday to provide the results of a week-long inquiry into allegations that Kavanaugh sexually assaulted female students while in high school and college - accusations he has angrily denied. Officials said the FBI could finish before Friday, particularly as senators clamor for information ahead of an expected first procedural vote on his confirmation this week.
FBI agents have completed a first batch of interviews of four individuals closest to the alleged events, and the White House has given the bureau a green light to conduct some further interviews, according to the people familiar with the matter.
On Tuesday, the FBI moved beyond those initial four people, interviewing Tim Gaudette, a Georgetown Prep classmate of Kavanaugh's. Gaudette's lawyer, Kenneith Eichner, said an FBI interview took place but declined to comment further. Gaudette's home was the site of a July 1, 1982, party that Kavanaugh references on his calendar and has become the focus of lawmakers' concerns.
FBI agents have also interviewed Mark Judge, a key Kavanaugh high school friend who has denied any knowledge of a teenage gathering like the one described by Kavanaugh's first accuser.
In the interview, Judge also denied recent allegations leveled by Julie Swetnick, saying he had no knowledge of anything like what she had claimed - that he, Kavanaugh or other male friends tried at house parties to get girls drunk in order to take advantage of them, according to two people familiar with the interview.
Another friend from Kavanaugh's high school days, Chris Garrett, has also completed an FBI interview, according to Garrett's lawyer, William Sullivan, Jr., who declined to comment further.
Discussions between the FBI and the White House are complicated by a number of factors - the president's long-running distrust of the agency over its Russia probe, the intense criticism by members of Congress of the FBI's handling of politically sensitive investigations, and the added difficulty of conducting an inquiry that could tip the scales in deciding who becomes the next member of the Supreme Court.
One political consideration looms larger than those issues, according to people familiar with FBI and administration deliberations: If the Democrats win control of the House, lawmakers could launch investigations into exactly what White House and bureau officials said internally about the Kavanaugh matter.
The White House and FBI "are being very careful with each other," said one person familiar with the matter, who, like others, spoke on the condition of anonymity to discuss sensitive deliberations. "Everyone realizes that they are under a huge amount of scrutiny, and will be when it's over, too."
Several people involved in the discussions said part of the challenge is in handling the Kavanaugh inquiry like a "regular" background check when the circumstances make it highly unusual.
In many background checks, interviews will be conducted by a single agent, but the Kavanaugh matter is anything but a standard inquiry.
When the FBI met one of Kavanaugh's accusers, Deborah Ramirez, in Boulder, Colorado, this past weekend, they sent two agents, and a supervisory agent waited in an adjoining room, according to people familiar with the matter.
John Clune, an attorney for Ramirez, said Tuesday on Twitter that his client spoke with the FBI for more than two hours Sunday in a "detailed and productive interview." The agents "were clearly motivated to investigate the matter in any way they were permitted," he added. But he asserted that Ramirez had provided the names and contact information of more than 20 witnesses who might be able to corroborate her allegation that Kavanaugh exposed himself to her at a party when they were at Yale, and that, as far as Clune knew, the FBI had not contacted any of them as of Tuesday.
"Though we appreciated the agents who responded on Sunday, we have great concern that the FBI is not conducting - or not being permitted to conduct - a serious investigation," he said.
Attorneys for Christine Blasey Ford, the woman who said she was assaulted by Kavanaugh when they were teens and who testified to the Senate last week, wrote FBI Director Christopher Wray on Tuesday to say they were concerned the FBI had not sought an interview with her.
"It is inconceivable that the FBI could conduct a thorough investigation of Dr. Ford's allegations without interviewing her, Judge Kavanaugh, or the witnesses we have identified in our letters to you," the lawyers wrote, demanding an immediate answer to what they said were days of silence from the FBI.
The bureau declined to comment.
The Kavanaugh investigation is being led by the FBI's Security Division, a component of the Human Resources Branch that is normally tasked with handling background checks.
Because the White House and even the president are dictating what the bureau should do, Wray is also involved in the matter, according to people familiar with the work.
Background checks are a mainstay of the FBI, but they tend not to be exciting - or visible - cases. They are often assignments given to younger agents to learn how to handle paperwork and conduct interviews.
The Kavanaugh investigation is playing out publicly - with lawyers for those who are interviewed often confirming that their clients have been talked to.
Some people have approached the bureau on their own, and at times been frustrated to be routed to a tip line or online reporting form. That is how the bureau normally handles voluminous tips in high-profile matters, but in a probe with a short deadline, the response feels inadequate to some.
Law enforcement officials said they expect to be attacked by whichever side dislikes the findings - or by both sides.
Since Trump ordered the background investigation reopened, the FBI has assiduously declined to comment, referring all questions about its work to the White House. Because the matter is a background check, rather than a criminal investigation, it is not inappropriate for the White House to call the shots.
"The bureau isn't going to make any conclusions, just gather the facts they can substantiate and write the reports and hand in their work," said Joe Lewis, a former senior FBI official who at one point in his career oversaw background-check investigations. "They're not going to play footsie with it or shade anything."
Joseph Campbell, a former FBI assistant director of the Criminal Investigative Division, said the bureau will probably do what it always does in political controversy: fall back on process.
"It is quite a situation," Campbell said. "They're going to continue to march on following that normal procedure, despite a lot of the other noise going on around them."
That is not to say there won't be challenges. Campbell said that in his experience with background checks or other investigations at the FBI, "I never encountered an instance where I was directed in regard to specifically talk to these people or don't talk to these people."
The bureau, too, cannot solve the political question of whether Kavanaugh should be a Supreme Court justice - no matter how much Democrats and Republicans might want it to.
"They're not going to form an opinion about what they identify, they're simply going to report that information," Campbell said. "What happens from there is really not in their control."