The Senate Judiciary Committee voted along party lines on Friday to bring Brett Kavanaugh’s Supreme Court nomination to a full Senate vote after Republican Sen. Jeff Flake called for a weeklong FBI investigation into the sexual assault allegations levied against the nominee before the final vote. President Trump authorized the supplemental investigation later in the day.

Democrats and Kavanaugh’s accusers have been urging Senate leadership over the past two weeks to recruit a neutral third party such as the FBI to interview witnesses and find more evidence that could prove or refute the nominee’s assertions of innocence.

To get a better sense of what exactly this time- and scope-limited FBI investigation might entail, I spoke to Barbara McQuade, a University of Michigan Law professor who formerly served as the U.S. attorney for the Eastern District of Michigan. Here is a transcript of the interview, condensed and lightly edited for clarity.

Aaron Mak: Does a week seem like enough time for the FBI to do this investigation?

Barbara McQuade: It does for this. I think they could probably do it in an even shorter period of time, like a few days. A week is reasonable because then if they are to reach out to these people tomorrow, they don’t have to say, “Drop everything and meet with me.” It gives them a few days to find the person, to meet with them, and then to write up the report. It’s a short turnaround time, but this has a finite scope. This is not asking Robert Mueller to conduct an investigation with long, complex ties to a foreign country. It’s a handful of people they’d like to interview.

How will the FBI approach the investigation? Who’s involved?

What usually happens is that someone would take ownership and come up with a list of the people who ought to be interviewed. This is usually what they call a “case agent,” who’s in charge of the investigation. I would imagine that someone from the Washington Field Office of the FBI would be charged with coming up with the list. Then they send leads to the local office where the people are located.

So they come up with the list. Say it’s Mark Judge and there are other people in Maryland, people in California, people wherever. They would then send a lead to those local offices: “Hey, California office, I would like you to interview these two people. Hey, Maryland office, here’s three for you. Hey, D.C. office, here’s two for you.” The FBI is a national law enforcement organization and has the benefit of agents all over the country. When they send those leads, they then assign them to an agent in that local office.

I’ve been involved in FBI background investigations both for myself and as someone who’s a witness for others, like judges. Frequently what will happen is that I’ll get a call from an FBI agent who will say, “I’m conducting an FBI background investigation of Person X. Could I come talk to you tomorrow, because they’ve only given me two days to do this investigation.”

It wouldn’t surprise me if they send several agents to conduct these interviews, reach out to these people, and arrange to meet sometime in the next few days. The agent will then go out to visit them at their home or an FBI office or a coffee shop—wherever is convenient. Then they have a long series of questions that have already been written out on a list.

Is there any other evidence that they’d be looking for, beyond interviewing witnesses?

I think they would be purely interviewing witnesses. It’s unlikely that there’s any physical evidence remaining from a sexual assault attempt that may or may not have happened over 30 years ago. Although it’s been suggested that Judge Kavanaugh should submit to a polygraph test, I think that would be highly unlikely and highly unusual. Polygraphs are used to assess the credibility of witnesses and defendants, but to ask him to do that strikes me as something they probably won’t do.

What stands out to you as the most promising lines of inquiry?

Mark Judge strikes me as the most interesting person here. He has seemed to work pretty hard to not testify. Judge Kavanaugh has seemed to be very uninterested in an FBI investigation. It makes me wonder why and what else could be out there.

I would think that Mark Judge would be pretty high on the list to ask him. He seems to be a person who could be very critical to the outcome here, especially in light of Dr. Ford’s testimony yesterday that when she saw him several weeks after the alleged incident, instead of greeting her the way he normally did, his face got white. It suggested to her that he was remembering the incident. If he remembered it then, might he still remember it today?

[After this interview was conducted, Mark Judge’s lawyer released a statement reading, “If the FBI or any law enforcement agency requests Mr. Judge’s cooperation, he will answer any and all questions posed to him.”]

There are also the people who submitted affidavits on behalf of Dr. Ford, who said she discussed it with them many years after it happened but before Brett Kavanaugh’s name was known to the public. That could be of interest. There’s a rule of evidence that says that ordinarily those statements are hearsay, but they are allowed when someone offers them to rehabilitate a witness whose credibility has been attacked.

What kind of report will the FBI produce in the end?

They’re known as FBI 302s, named after the form on which they used to be printed. The agents write a report of the interview and it’s really just facts. It doesn’t provide any analysis. It’ll just say, “On such and such date, on such and such time, I interviewed the witness at this location. I first identified myself as an agent and warned them that lying is a crime.” And then they would proceed to summarize all of the things that the person said.

Kavanaugh and others suggested during yesterday’s hearing that we’re not going to find out that much more from an FBI investigation, especially since a lot of these witnesses have sent in statements. Do you think that’s true?

I don’t buy that. As we saw in the testimony of Dr. Ford and Judge Kavanaugh, live testimony and questioning is so much more probative than written answers. Written answers can be drafted either with the assistance of, or entirely by, a lawyer. There’s no opportunity for follow-up questions.

There’s no opportunity to look at tone and observe inflection and body language. It could be what allows an experienced questioner to follow up on things. I don’t know if they will assess the credibility in the report, but as they ask questions, they might say, “You paused there. Why did you pause? Let’s go back over that. Are you sure you’re accurate when you say X, Y, and Z?” They can use what they’re observing to ask meaningful follow-up questions. Going out and making these observations and interviewing these people with follow-up questions could be revealing.

And I think even if it’s not, the process is very important. Even if they say, “We talked to all these people, here’s the information, and we still can’t reach a conclusion as to what happened,” I think it will satisfy at least some people who want there to be a fair process. It would satisfy me that they have done all they can do to investigate this matter. To go through this for just one week and thoroughly investigate all that we know would give people some comfort and help maintain the legitimacy of the court that has to decide issues of credibility and literally issues of life and death in capital cases.