Mueller's Reputation In Washington Is 'Stunningly Bipartisan,' Journalist Says

TERRY GROSS, HOST:

This is FRESH AIR. I'm Terry Gross. Although the nation's attention is focused on special counsel Robert Mueller and his investigation into the Trump campaign and Russian interference in the 2016 election, Mueller himself has managed to pretty much stay out of public view. Many of us know little about him. My guest Garrett Graff can help fill us in. His 2011 book "The Threat Matrix" is about the FBI under Mueller's leadership. Mueller was appointed by President Bush and continued to serve under President Obama, becoming the first FBI director since J. Edgar Hoover to complete his 10-year term. Obama then reappointed him for a special two-year term, which required a special act of Congress. Mueller's first day on the job was a week before 9/11. Graff says that after 9/11 Mueller transformed the FBI.

Graff has been following the special counsel's investigation and has some thoughts on what Mueller's tenure at the FBI, including a showdown with President Bush, can tell us about his approach to leading the current investigation and how he might respond if President Trump tries to directly pressure him or fire him. Graff is a contributing editor at Wired. His latest story's about what might happen if Mueller gets fired. News stories about the Mueller investigation, President Trump and the House Intelligence Committee are breaking at an incredibly fast pace. At the time we recorded this interview, the Nunes memo was expected to be released very soon.

Garrett Graff, welcome back to FRESH AIR. Now, I bet when you were writing about Robert Mueller, that you never expected that he would be relevant in the kind of context he's relevant in now.

GARRETT GRAFF: Absolutely. Up until probably about a year-and-a-half ago or two years ago now, I was I think maybe the only person in the world who had closely followed Jim Comey and Bob Mueller's careers.

GROSS: So he was appointed by President Bush - Mueller was. He's a Republican. Was he considered partisan during his years in the FBI?

GRAFF: No, Bob Mueller is probably about as apolitical and nonpartisan a figure as you could find in Washington, particularly at the levels of government in which he has served. And we know him, you know, most recently obviously as the FBI director. But his tenure in government really dates back to the Reagan years. And he's been appointed or held top jobs in the administrations of all five of the last presidents and was appointed to the Justice Department, the head of the Criminal Division under George H.W. Bush's administration then was appointed a U.S. attorney by Bill Clinton then appointed the acting deputy attorney general by George W. Bush and then later FBI director, a position that he was reappointed to in an unprecedented move by President Obama and confirmed by the U.S. Senate by a vote of 100-0. I mean, that is sort of a stunningly bipartisan track record in today's times.

GROSS: So he started as head of the FBI just a week before 9/11. I mean, it was September 4, 2001. When he started, you say he thought his first mission was going to be overhauling the IT system at the FBI. What were the problems with the computers and the computer networks at the FBI when he took over?

GRAFF: Yeah, you're exactly right. Sort of the strangeness is that Bob Mueller probably would have never been the nation's top choice for a job leading counterterrorism-focused intelligence agency. He came up primarily on the criminal side although he did oversee the prosecution of the bombing of Pan Am 103 earlier in his career. And he came in to the FBI in part in the summer of 2001 because he was known inside the Justice Department as a computer guy. He had helped found the Justice Department's first real computer crime unit.

And the FBI in the summer of 2001 had this incredibly outdated and antiquated computer system. I mean, it's so bad that at one point that summer as they were - as FBI agents were literally chasing the Al-Qaeda terrorists that we now know were planning the 9/11 attack, in order to get a file from the Los Angeles office to New York City, a FBI agent actually had to save it to a floppy disk and then fly cross-country to New York in order to deliver it in person. And then in the wake of 9/11 actually, the FBI had no method by which to attach a file to an email. And so they had to FedEx pictures of the 9/11 hijackers out to their field offices around the country.

GROSS: Can I just pause here and say how remarkable that is. I really hate to think that I had a better computer than the FBI did.

GRAFF: Exactly. And so that was when Mueller was taking over in the summer of 2001 - what he thought his top priority was going to be. And he was actually sitting in the FBI director's conference room on the morning of September 11 receiving his first briefing on Al-Qaeda and the investigation into the bombing of the USS Cole, which had happened the year before, when they got word of the first plane hitting the World Trade Center. And he told me later that he remembers sort of looking out the window at the beautiful blue day that we had here on the East Coast that day, as everyone remembers, and thinking how could an airliner have plunged into the World Trade Center on such a clear day.

GROSS: Yeah, well, he found out pretty soon how that happened. So he did not have counterterrorism experience, but one thing he did have that I assume helped him in leading the FBI after 9/11 was that he had a military background. He was used to being under fire. He was not a fearful person. Can you just talk briefly here about his military record.

GRAFF: Yeah, part of what makes Bob Mueller such a fascinating character is he has dedicated his life, sort of time and again, to public service. He went to prep school, actually with John Kerry, at St. Paul's in New Hampshire then went to Princeton and was inspired there by the model of one of his older classmates, someone named David Hackett, who signed up to go to Vietnam and was killed in Vietnam. And Hackett's method or model of service and sacrifice inspired Mueller and a handful of other colleagues to sign up for Vietnam after college. This was early in the 1960s, so this was before Vietnam became quite the cultural touchpoint that it did later.

And 2nd Lt. Marine Corps Bob Mueller ended up leading a platoon in the jungles of Vietnam for a year and really distinguished himself in combat. He received a Bronze Star with Valor for his leadership in ambush that his unit suffered in the fall of 1968 and then was actually shot himself in a separate incident in April, 1969, where he received, of course, the Purple Heart, and was quickly back on patrol and served out the remainder of his year.

GROSS: So you tell a story shortly after 9/11 that Mueller is at a meeting hearing strategies from the cabinet and the National Security Council - this is in the White House - about what to do after 9/11. So Mueller warns the people offering their strategies that if we did some of the things that they're suggesting, it may impair our ability to prosecute. And then John Ashcroft says this is different. What did Ashcroft mean?

GRAFF: Bob Mueller in the days after 9/11 sees this incredible sea change in the mission of the FBI, which until then for most of its first 90 years had primarily been a law enforcement agency focused domestically on solving crimes after the fact. And on 9/11, we saw an international plot that focused on a suicide attack with catastrophic results and that that necessitated this top-to-bottom change in the way that the United States approached counterterrorism issues - that after-the-fact investigation was going to be inadequate in the face of these threats.

And so Mueller was given a mission by John Ashcroft and President Bush to not just investigate attacks afterwards but to stop plots in the first place, to disrupt the attack before it happened. And it led to this massive reorganization that Bob Mueller spent the next 12 years of his tenure working on to move the FBI from what was traditionally a domestic law enforcement agency into something that is more akin to an international intelligence agency.

GROSS: Let's take a short break here, and then we'll talk more about Robert Mueller and his background. If you're just joining us, my guest is Garrett Graff. He's a journalist who, among other things is, the author of the book "The Threat Matrix: Inside Robert Mueller's FBI," so he knows a lot about Robert Mueller. We'll be right back. This is FRESH AIR.

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GROSS: This is FRESH AIR. And if you're just joining us, my guest is Garrett Graff. We're talking about Robert Mueller. Graff is the author of an earlier book called "The Threat Matrix: Inside Robert Mueller's FBI." And Robert Mueller became the head of the FBI one week before 9/11 and stayed for 12 years as director of the FBI. And he transformed the FBI.

So it looks like Robert Mueller in his role as special counsel is heading to a showdown with President Trump. Trump might be moving through one means or another to shut down the investigation that Mueller is leading. We'll see what happens. We don't know. Everybody's trying to read the signs. But we can look back and see what the showdown was like when Mueller had a showdown with President Bush while Mueller was head of the FBI.

So this was about a secret surveillance program called Stellar Wind. And at the time that the Bush administration was seeking reauthorization of this secret program, John Ashcroft, who was the attorney general and who had to reauthorize it, was in the hospital recovering from gallbladder surgery which he had just had. Knowing that he'd be incapacitated in the hospital for a time, he had signed over his duties to his number two, who was James Comey. So describe the hospital scene.

GRAFF: Yeah. So this was a showdown that had been unfolding entirely in secret. We had no idea publicly that any of this was going on since Jim Comey took over as deputy attorney general in the - at the end of 2003. This program, known as Stellar Wind, it was an NSA domestic surveillance program, had been authorized every 90 days by the Justice Department and required to be reauthorized every 90 days by the Justice Department.

And as Jim Comey was getting up to speed on the program, there were some problems that had been pointed out to him. And he began to fear that the program actually, as currently in operation, was unconstitutional. He had taken these concerns to the White House with the full support of John Ashcroft and the head of the Office of Legal Counsel inside the Justice Department who was then someone named Jack Goldsmith. The Office of Legal Counsel is sort of the Justice Department's own top in-house lawyers.

And the - Vice President Cheney had argued very vociferously that this program was critical to the nation's security and had almost literally told Jim Comey that if you don't reauthorize this program, people will die. And yet, then John Ashcroft goes into the hospital. Jim Comey is left as acting attorney general as this is coming down to the wire. And Jim Comey says that he's not going to reauthorize the program. And Jim Comey is driving home.

This is March, 2004. Now Jim Comey is driving home with his U.S. Marshals security detail and gets a telephone call from John Ashcroft's wife from George W. - from George Washington Hospital and says the president has just called and he's sending over then-White House Chief of Staff Andy Card and White House counsel Alberto Gonzales to meet with John Ashcroft.

GROSS: So Comey gets really afraid of this because it's a kind of sneak reauthorization?

GRAFF: That this an end-run around Comey's authority. And he turns on the lights and siren in his motorcade and begins to race towards G.W. Hospital. And his first telephone call is to Bob Mueller, who is also at home in Georgetown having dinner that night. And he gets Mueller on the phone, explains to him what's happening, asks Mueller to come to the hospital.

And then, in what I think is sort of the - has to be one of the most surreal telephone calls in the history of the U.S. government, expresses the fear to Mueller that Secret Service agents who are presumably going to be accompanying Andy Card might try to remove Jim Comey from the hospital room. And he doesn't want John Ashcroft to be left alone and isolated with the White House staff. And so he asks Mueller to instruct the FBI agents guarding John Ashcroft to not allow under any circumstances Jim Comey to be removed from the room.

GROSS: So Andy Card is bringing Secret Service agents, but Comey wants Mueller to tell FBI agents to prevent the Secret Service agents from ousting Comey?

GRAFF: Exactly. And, I mean, you can just sort of imagine what it must have been like for the agents on that security detail. You know, they're in this dark and empty wing of George Washington Hospital thinking that they're about to have the quietest night of their careers. And they get a telephone call from the FBI director himself saying resist the Secret Service that are coming with the White House chief of staff.

I mean, just sort of an incredible moment to sort of put yourself in that hospital room. Then everyone's racing towards the hospital room, you know, lights and sirens going. Comey gets there first, shortly before Andy Card and Alberto Gonzales. They go to John Ashcroft's bedside, ask him to reauthorize the program. John Ashcroft sort of lifts his head up off the pillow.

GROSS: Is he sedated at this point?

GRAFF: He's sedated. He is, by sort of all accounts, relatively confused about what's going on. And he says, you know, my thoughts don't count. I'm not the attorney general, he is. And Ashcroft points to Comey in the corner. And Andy Card and Alberto Gonzales just leave the room. Bob Mueller gets there a few minutes later. Ashcroft says, you know, Bob, I don't really understand what's happening. And Bob Mueller says, you know, John, there comes a time in every man's life when he's tested. And tonight, you passed the test.

GROSS: And then Mueller faces a test, too. He ends up - yeah, go ahead.

GRAFF: This very quickly spirals over the next 48 hours. John Ashcroft is, you know, still in the hospital. Bob Mueller and Jim Comey both prepare letters of resignation. They are, you know, they think it's unconstitutional that this program is in existence and they can't abide by that. And in the midst of this week, there's the Madrid train bombings. You know, you have this massive al-Qaida-led attack that very clearly points out the stakes of what happens if a terrorist plot goes undetected.

And Jim Comey and Bob Mueller head over to the White House to brief President Bush on the Madrid train bombings and what's unfolding. And Jim sort of says at the end of the meeting, you know, that he needs to talk to President Bush for a couple of minutes and lays out his concerns privately. And he says, you know, Mr. President, I need you to know that Bob Mueller is prepared to resign as well.

And as the story has been related, Jim Comey sees sort of President Bush, you know, almost visibly blink and recoil at this. He knows in his heart how damaging that could be to his presidency. And he knows Bob Mueller's reputation as a sort of black-and-white, stand-up, truth-and-justice kind of guy. So this immediately becomes something that is incredibly serious at the White House.

And so President Bush sends out Jim Comey, brings Bob Mueller in. Bob Mueller explains his own comments and concerns about the Stellar Wind program. And President Bush, you know, literally blinks and he says, you tell Jim to make the changes that Jim thinks are necessary. And it took a couple more days to sort of fully unfold, but the situation was diffused. And it didn't come out until years later after Jim Comey was out of government and once Alberto Gonzales had actually moved over to be the attorney general in the wake of John Ashcroft's departure.

GROSS: So in a way, the moral of this story is that Mueller tried to stand up for his principles and he didn't blink. And it was President Bush who kind of backed down and said, OK, we will not reauthorize the program.

GRAFF: Exactly. And also, I think sort of an important second lesson is the respect with which everyone in Washington - in the administration at that point - held Bob Mueller, which is that they knew that this was not someone coming with any sort of partisan agenda. This was not anyone who was coming to play any politics. This was someone who in sort of a fascinatingly black-and-white way sees and has dedicated his life to the pursuit of justice and the protection of the Constitution.

GROSS: My guest is Garrett Graff. His books include "The Threat Matrix," which is about Robert Mueller's tenure as director of the FBI under Presidents Bush and Obama. Graff is also a contributing editor at Wired. After a break, we'll talk about what might happen to special counsel Mueller's investigation if he is fired. I'm Terry Gross, and this is FRESH AIR.

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GROSS: This is FRESH AIR. I'm Terry Gross, back with my guest, Garrett Graff. We're talking about special counsel Robert Mueller and what we can learn about him and his leadership style by looking at his tenure as FBI director under Presidents George W. Bush and Obama. How Mueller transformed the FBI is the subject of one of Graff's books titled "The Threat Matrix." Graff is a contributing editor at Wired. His latest piece is about what might happen if Mueller is fired. At the time we recorded this interview, the Nunes memo was expected to be released very soon.

So I want to read something that you quote from Robert Mueller. And remember, Mueller takes over as head of the FBI right before 9/11 and is faced with many difficult questions. And he says, (reading) we live in dangerous times, but we are not the first generation of Americans to face threats to our security. Like those before us, we will be judged by future generations on how we react to this crisis. And by that, I mean not just whether we win the war on terrorism - because I believe we will - but also whether, as we fight that war, we safeguard for our citizens the very liberties for which we are fighting.

Why did you quote that?

GRAFF: I think it's sort of an interesting example to me of the way that Bob Mueller has put the Constitution and defending the Constitution at the center of so much of the work that he has done, that this is someone who really, truly believes in sort of truth, justice and the American way in a way that very few people in American life today anymore do. I mean, I had - one of his aides said to me at one point that sort of Bob Mueller seems like a figure who has stepped right out of the history books. And I think we sort of see that both in the way that he comported himself during his career and even today as special counsel, that this is not someone who in any way has tried to grab the spotlight but instead has sort of kept his head down and worked hard throughout his career.

He sort of echoed a similar sentiment when he was speaking at the FBI's hundredth anniversary when he said, you know, it is not enough to stop the terrorist. We must stop him while maintaining his civil liberties. It is not enough to catch the criminal. We must catch him while respecting his civil rights. It is not enough to prevent foreign governments from stealing our secrets. We must prevent that from happening while still upholding the rule of law. The rule of law, civil liberties and civil rights, these are not our burdens. They are what make us better.

GROSS: After 9/11, some critics on Capitol Hill and people within the 9/11 Commission were suggesting that the FBI, now that it had a dual role, be divided into two separate agencies, one that dealt with the traditional FBI duties of prosecuting domestic criminals and the other that would be a counterterrorism agency. Mueller pressed for both of these functions to remain under the umbrella of the FBI. Why did he want them to remain FBI functions?

GRAFF: This was what was known as the MI5 model, which is the British domestic intelligence agency, and the way that Britain in the U.K. separate these is that, you know, they have Scotland Yard as effectively the national law enforcement agency and then MI5 as the domestic intelligence agency. And there was a big push both on Capitol Hill and then among members of groups like the 9/11 Commission to consider that same model here in the United States, the thinking being that effectively - and I'm oversimplifying obviously a very complex argument - that we couldn't respect all of the legal niceties of law enforcement in order to pursue terrorism with the vigilance that we needed after 9/11 and that - Mueller just fundamentally disagreed.

I mean, he is - both as the sort of person in charge of protecting the bureau but also as a lifelong Justice Department insider, he really believes deeply in the mission of the Justice Department and that the attorney general has this unique dual role, not just as the nation's top law enforcement officer but also the top sort of protector of the Constitution, and that he saw it as being incredibly important that the FBI be grounded inside the Justice Department, that it be grounded reporting to the attorney general, keeping this close constitutional watch on the FBI's activities and, in fact, was able to deflect the attempts to break the FBI in two, in part just because of the respect that people had for Bob Mueller, that he asked for the time to make the transition and the transformation inside the FBI and was given it and by most accounts has succeeded.

GROSS: So Mueller was afraid that if counterterrorism was moved to another agency, that agency would likely be outside of the jurisdiction of the Department of Justice, and therefore, it might be more likely that there would be constitutional violations without that oversight.

GRAFF: Yes. And he also just felt it was more important - that it was sort of also really important for the FBI with its dual intelligence capabilities and its dual law enforcement capabilities to be the partner for state and local officials and law enforcement agencies, that he really saw actually that unity of mission as a strength, not a weakness, that the FBI was able to bring both intelligence capabilities and law enforcement capabilities to an investigation as it was necessary.

GROSS: You've told a couple of stories about Robert Mueller standing up for his principles. What was Mueller most criticized for during his tenure at the FBI?

GRAFF: There were a number of different controversies that sort of cropped up for him. I mean, we talked a little bit about the challenge of the FBI computer system, which was a perennial challenge that - actually sort of Bob Mueller's efforts to revamp the computer system failed repeatedly at actually a cost of literally hundreds of millions of dollars in cost overruns and unused, failed programs. And it really took him most of the 12 years that he was FBI director to sort that out and get that program back on track.

Moreover, I think that there was a not insignificant amount of criticism inside the bureau about his leadership style. I mean, he led the FBI effectively as a Marine combat commander. I mean, he drove the bureau sort of harder and longer and faster than it had probably ever been driven or had to change in its history and was seen as very gruff and brusque in his dealings with employees. Sort of one of the things that really endeared Jim Comey to the workforce when he took over from Mueller was sort of what a gregarious, fun guy Jim Comey actually is. You know, he would go down to the cafeteria to have lunch with the, you know, sort of the regular folk in the FBI offices. And he would sort of wander the halls chatting with people in a way that Bob Mueller never did.

And some of that was a reflection of the era. I mean, on a daily basis, you know, Bob Mueller and the other leaders of the national security agencies in the United States really felt that the country could be just hours or days away from the next terror attack. I called my biography of Mueller "The Threat Matrix" because it's the name of the document that Mueller and Justice Department officials began every morning after 9/11 reviewing. It was this Excel spreadsheet - I mean, literally, that's all it was - listing every terror plot and terror attack that the intelligence community was tracking that morning. And some days, it was dozens of pages long. And so, you know, everyone would begin their morning sort of running through these worst-case scenarios of what could be unfolding that day. And it's actually the sort of moment that we forget about today just how dark those days came.

GROSS: So let's take a short break here, and then we'll update the story and talk about Robert Mueller as special counsel. If you're just joining us, my guest is Garrett Graff, and he's the author of an earlier book that's a biography of Robert Mueller called "The Threat Matrix: Inside Robert Mueller's FBI." We'll be right back. This is FRESH AIR.

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GROSS: This is FRESH AIR, and if you're just joining us, my guest is Garrett Graff, and he's the author of a book that was published a few years ago called "The Threat Matrix: Inside Robert Mueller's FBI." We invited him on the show to talk about Robert Mueller now that Robert Mueller is at the center of national attention as the special counsel investigating connections - possible connections between the Trump campaign and Russia. Now, things appear to be heading toward a showdown between President Trump and Robert Mueller.

So as you look at how Robert Mueller is handling his role as special counsel and dealing with all of the attempts of the House Intelligence Committee led by Devin Nunes and the Trump administration to try to discredit the investigation, what connections do you see between how Mueller is handling the situation now and how you saw him handle it when he was FBI director?

GRAFF: I think that there are a couple of different things that stand out to me - really sort of three big lessons that we can see already playing out in the investigation. The first is that this is, in many ways, a perfectly standard and routine FBI investigation. The FBI, as an investigative agency, takes down corrupt organizations. You know, that's sort of what it is designed to do, you know, go after street gangs, drug cartels, organized crime families. And the way that they do that is by starting on the outside and working their way in. And so that can either mean starting at the bottom of an organization or starting with sort of ancillary charges and sort of working their way inwards, sort of the equivalent of, you know, getting Al Capone for tax evasion.

And so you've seen that in this investigation both where Mueller has started, you know, almost literally at the bottom with George Papadopoulos and sort of pressured him to cooperate on people above him, and then also in the charges against Paul Manafort, which are sort of ancillary to the core question of the behavior of the Trump campaign. He's sort of first charged this decade-long alleged money laundering scheme dating back through some sort of unrelated work, again, as a pressure point on Paul Manafort and Rick Gates.

The sort of second thing that stands out to me that is very indicative of the way that Bob Mueller has operated is that he at every stage of this investigation has demonstrated that he knows far more than we think he does. You know, that sort of for all of the attention and the focus and the coverage of this investigation, it's clear that Bob Mueller is actually running a very leak-free ship, and that's partially a reflection of his desire and tendency to stay out of the spotlight, you know, keep his head down and just keep plodding ahead. And it's the professionalism of the team that he has surrounded himself with - I mean, many of whom he has worked with in the past. And Aaron Zebley, his former chief of staff, is right there alongside him - Andrew Waisman right there alongside him, his former general counsel - and that he has, you know, sort of surprised us with every stage of this investigation.

I mean, the fact that George Papadopoulos had been arrested, cooperated and pleaded guilty all in secret was a huge surprise. Even more recently, the news last week that actually Jim Comey had been interviewed and testified before the Mueller team several weeks ago was a big surprise to people. We know that Bob Mueller knows a lot more than we think he does. There are at least two major pieces of evidence that have not yet become public - whatever it was that George Papadopoulos traded for his plea deal and whatever it was that Michael Flynn, the former national security adviser, traded for his plea deal. I mean, neither one of those pieces of information have become public. But we know that they must be relatively significant in order for Mueller to offer the plea deals that he did.

And then the third thing that stands out to me is just sort of how tenacious and thorough the investigation has been. We sort of speak of the Mueller probe as if it is one thing, but it's actually this whole panoply of different investigations into different threads of the Trump campaign, the 2016 presidential election and the involvement of Russia. You know, there are sort of some money laundering aspects to it. There are some campaign aspects to it. You know, we've seen him go after and get documents from Facebook, other social media sites, Cambridge Analytica, the campaign's sort of data team. There are sort of all sorts of different threads of this investigation that are being followed. And we know that Bob Mueller is going to be incredibly tenacious in that investigation but that he's also not going on a fishing expedition.

GROSS: As we record this interview, there's a lot of things that we don't know that might happen soon. We don't know if the Devin Nunes memo is going to be released by the president. We don't know because it's up to the president to decide. We don't know if the president will fire Rod Rosenstein, who is overseeing the special counsel's investigation. We don't know if the president will fire the special counsel himself. Those are really huge questions that we don't know the answer to. Are you speculating to yourself what possible outcomes might be?

GRAFF: I think there are just too many moving parts right now to understand, you know, all of the different scenarios that could unfold, in part because what we also know is that the president is sort of impulsive in a way that makes any type of prediction of his behavior incredibly difficult, where, you know, we could all be in absolute agreement today that Bob Mueller will never be fired, and then the president happens to be watching "Fox & Friends" tomorrow morning, and get angry and, you know, fire off a tweet, you know, that says who knows what.

And what I do think is important though is that I have to assume, knowing what I know about Bob Mueller and the team that's around him, that they have been thinking about that question from the very first days of this investigation. And I would be very surprised if they have not been carefully considering at each step of their investigation how to ensure the survival and longevity of their investigation whether or not Bob Mueller himself is there leading it.

GROSS: But this leads to something I've been wondering. If the president terminates the investigation, you know, or fires Robert Mueller or has somebody else fire Robert Mueller, Robert Mueller knows a lot. He has gathered thousands and thousands of documents. What happens to what he knows? The documents, I assume, would not travel with him if he is forced out. But if the investigation ends or if it's taken over by somebody else, what happens to what's in Robert Mueller's brain? Are there any legal restrictions for him to tell what he knows?

GRAFF: There are legal restrictions, obviously, around the dissemination of classified information, but it's important to think of this not as what is in Robert Mueller's mind, which is, of course, important. But these are in FBI investigative files, so those files don't go away. Those agents don't go away. This was an investigation that began before Robert Mueller was appointed special counsel. I mean, remember, actually, the guilty pleas of George Papadopoulos and Michael Flynn both stem from lies that they told to FBI agents, you know, months before Robert Mueller stepped into this probe. And so those investigators would presumably continue investigating, and there might even be a - you know, a new special counsel appointed who steps in.

And even if that's not true and that the - sort of the special counsel's office is disbanded entirely, the prosecution of those open investigations would likely transfer back to the U.S. attorney's office in D.C. or the U.S. attorney in the Eastern District of Virginia - in Alexandria, Va., and that those investigations might just continue apace absent a special counsel. You know, people sort of forget or don't know the - when you open an FBI investigation, that's actually a very formal process that goes through sort of several different stages of an investigation before you end up with what's known as a full field investigation. And by the time you get there, you have to have shown evidence of a potential criminal act in order to get to that formal OK to continue an investigation.

And then sort of similarly, there's a formal process to shut down an investigation that requires prosecutors to review the evidence with agents and to decline an investigation and charges. And so this is not something that is sort of quite as simple as, you know, if Bob Mueller is fired, he walks out the door, locks the office behind him, and everything just disappears into the ether.

GROSS: If you're just joining us, my guest is Garrett Graff, and he's the author of an earlier book that's a biography of Robert Mueller called "The Threat Matrix: Inside Robert Mueller's FBI." We'll be right back. This is FRESH AIR.

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GROSS: This is FRESH AIR. And if you're just joining us, my guest is Garrett Graff, and he's the author of a book that was published a few years ago, called, "The Threat Matrix: Inside Robert Mueller's FBI."

You wrote in a recent article that assuming, you know, Mueller's allowed to continue the investigation, that we shouldn't expect a kind of Perry Mason, gotcha outcome. Why not?

GRAFF: Two things. One is most federal cases don't result in public trials, you know? They're settled in plea deals sort of long before a public trial. And we've already seen that with Michael Flynn and George Papadopoulos in this case. But moreover I think the bigger thing is that Bob Mueller's investigation is only focused on federal crimes - you know, that's what he is investigating. That's what the FBI investigates - and that President Trump's behavior on the campaign and as president is really more of a political question. So there might very well be behavior that Mueller finds that he reports to the Justice Department and then they turn over to Congress that might very well be evidence of something short of a crime, but it's still behavior that we don't believe that the president of the United States should be engaged in. And so it could lead to impeachment proceedings or political pressure for the president to step down, even if it's not, you know, provable beyond a reasonable doubt in a federal courtroom that the president committed a federal crime.

GROSS: After President Trump fired James Comey, who was the head of the FBI, Comey, through whatever channels, managed to leak notes that he took about a meeting with Trump. And I keep wondering, like, if Mueller is fired, you say Mueller is a note taker in the same way that Comey is, that they both document everything. If Mueller is fired, there are notes that he's taken that wouldn't be classified in the way that many of the documents he's collected are classified. So I keep wondering, would he leak things from his notes?

GRAFF: I don't think, knowing Bob Mueller, that we would ever see Mueller leak. You know, he doesn't believe that that is sort of his place. He has - as someone who has spent many years trying to get information out of him, I can tell you he is...

GROSS: (Laughter).

GRAFF: ...Deeply reticent to share, you know, almost anything, you know, and tries to avoid the spotlight. But what could happen very well is that he be, you know, subpoenaed to appear before Congress, as Jim Comey was after he was fired, and that there is nothing that can stop the Trump White House or the administration from stopping Bob Mueller from speaking publicly as a private citizen once he is no longer in government. And so he could certainly be called to testify under oath on Capitol Hill either in open session or in closed session to discuss classified matters. And I think it would be hard to imagine that through one way or another that the information that Bob Mueller is able to explain does not become public knowledge down the road.

GROSS: Well, Garrett Graff, it's great to talk with you again. Thank you so much.

GRAFF: My pleasure. Thanks for having me.

GROSS: Garrett Graff's book about the FBI under Robert Mueller is called, "The Threat Matrix." Graff is a contributing editor at Wired. If you'd like to catch up on FRESH AIR interviews you missed, like our interview about Trump's former campaign manager, Paul Manafort, and how he made and lost a fortune representing authoritarian leaders working with oligarchs and putting money in tax-free offshore accounts, check out our podcast. You'll find lots of FRESH AIR interviews.

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GROSS: FRESH AIR's executive producer is Danny Miller. Our interviews and reviews are produced and edited by Amy Salit, Phyllis Myers, Sam Briger, Lauren Krenzel, Heidi Saman, Therese Madden, Mooj Zadie, Thea Chaloner and Seth Kelley. I'm Terry Gross.

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