Claire Fraser-Liggett: “This Is Not an Airtight Case By Any Means”


October 10, 2011
Director of the Institute for Genome Sciences, Fraser-Liggett was brought into the investigation to try to trace the DNA found in the anthrax attack letters back to its source material. Based on her team’s research, the FBI zeroed in on a flask controlled by Dr. Bruce Ivins. But while Fraser-Liggett believes the scientific evidence is “very solid,” she is not convinced the government has made its case against Ivins. This is the edited transcript of an interview conducted on June 14, 2011.

How did you get involved with the investigation? …

We had been working on deciphering the first genetic blueprint for the anthrax bacterium at the time that the letters were sent. …

We were the only ones in the world carrying out that kind of project at the time, so when the news broke about the letters, it became pretty clear that we might have a role to play.

Very quickly we were approached by colleagues from a number of the federal agencies: the [National Institutes of Health], the [Centers for Disease Control and Prevention], and also from the FBI, asking us … would we be able to think about helping with this investigation?

The idea is that molecular genetics could find the fingerprint or somehow lead to the perpetrator? …

The idea behind all of this was that the application of molecular genetics approaches might provide the kind of information that would help to link the material that was sent in the mail back to a source and back to the perpetrator.

And the idea is very much like the way that DNA sequence is used in human forensics today. You look for sequence variance and you look for matches, and it’s a matter of probabilities.

“If we could find molecular differences that held up and could be traced back to a potential source, that would potentially provide the smoking gun and say, ‘This is where the material came from.'”

This new field of microbial forensics that we were involved in was really being developed in real time. We were having to figure out what to do on a week-by-week basis.

… What was the state of the investigation when they first come to you? Do they know the direction they’re going? Do they understand the science? … The pressure to figure this thing out must have been intense.

When all of this broke and the news of the anthrax letters became public, it’s important to remember that this was a matter of weeks after 9/11. … It was a very confused and very frightening time.

What was going on? Is this it? Or is something else going to happen? Was there possibly a link between the events of 9/11 and the anthrax mailings?

So I don’t think it’s any exaggeration to say that the people within the FBI that were put in charge of this investigation were really scrambling to figure out how to put a master plan together that would guide this investigation. …

Did the FBI understand the science? Did they have the capabilities themselves to undergo this investigation?

The FBI absolutely understood the science, but at the time they didn’t have the capabilities in-house to do any of the work. So they knew immediately that they had to go outside.

… When they first came to you, what was the prevalent view? At that point, had they figured out that it was probably an American scientist? Were they still thinking it was Al Qaeda?

Fortunately, in the very early days of the investigation, Paul Keim at the University of Arizona was able to use some of the methods that he had developed to identify this as the Ames strain of the anthrax bacterium. Knowing that immediately put some likely constraints around the possible source.

Ames is not found widely distributed around the world. It was originally identified in the carcass of a dead cow in Texas in 1981, had been sent to USAMRIID [United States Army Medical Research Institute of Infectious Diseases], and it was a strain that was used in a lot of laboratory investigations around the world.

So the sense was — although it was just a best guess early on — that the source of the material was likely from a lab somewhere in the world that had gotten access to this strain over the previous 20 years.

Did you have any meetings with the FBI at that point where everybody’s sitting around the table saying: “OK, this is our best guess. This is what we need to do”? …

… For probably the better part of two years, once we got started, we would have weekly meetings. We would come in, and we would review progress. We would come up with a plan of attack for the next week or two.

Everybody then went back to their respective corners and tried to get their jobs done as quickly as possible. We were in constant communication with the FBI as all of this got under way.

Take us into one of those earlier meetings, the mood that pervaded it and how the FBI defined what they were doing.

The FBI was pretty clear in terms of what they wanted to try and accomplish by using these molecular genetics approaches.

Nobody knew for certain whether they would be successful, but the technology existed to be able to test whether or not we could find information encoded in the DNA sequence of the spores that were sent through the mail that could be used as a way to trace back to a potential source flask and do attribution. …

We had a lot of discussions about how would we do this. And then we really went into a self-critical mode: “OK, this is what we think will work. What are the flaws? What are we missing? What else should we be doing?”

We were repeating this almost on a weekly basis, so we were continually refining our thinking and our approaches and our priorities based on work as it proceeded in real time.

Talk about the pressure.

The pressure was enormous. For most academic scientists like myself, you never find yourself in a situation like this. … This was a criminal investigation. That was made clear to us early on.

We had to go through extensive training about how to revise the way we kept lab records. We had to demonstrate that we could keep all the material under a lock and key and make sure that only a small number of individuals had access to it.

We became familiar with the idea of chain of custody. When material comes in the door, you know who’s touched it, who’s had access to it, all the way through the entire process. That’s not the way that academic science is usually done. …

Talk about the pressure that you saw the FBI investigators were under.

In our weekly meetings with the FBI, it almost became painful to go into each of those meetings, because we knew how much pressure we were under, but that was nothing compared to the pressure that our FBI colleagues were facing.

These meetings were incredibly tense. They were very focused. There wasn’t a moment of time wasted. … I don’t think there was ever a moment of levity or even a sense that anybody could let their guard down for a moment. …

Why the pressure on the FBI?

A lot of infrastructure wasn’t in place at the time that this happened to really guide this kind of investigation. So I think there was a sense — and it was well publicized, and it was discussed — that this new field of microbial forensics that we were involved in was really being developed in real time. We were having to figure out what to do on a week-by-week basis.

You’re doing that in a situation where there was a tremendous amount of panic — a lot of concern on the part of the U.S. public; Congress had been shut down; the postal service had been shut down; we didn’t know what was going to happen next — and everybody wanted answers, and they wanted the answers yesterday. … The pressure just to keep everything straight, to keep everything quiet, had to have been enormous.

One of the things that was very clear to us is that we were working in partnership with the FBI but doing a very specific part of this, carrying out a very specific part of this overall investigation. We did not ever know any more than we needed to know to do our job.

It was only after all of this came to light, initially with the suicide of Dr. [Bruce] Ivins and then subsequently with the release of the National Academy [of Sciences] report, only then did it become clear to me, and I think to the other people who were working with me, how many different parts of this investigation the FBI was having to manage. …

The initial avenue of research that you guys were endeavoring upon didn’t go where you expected it. Explain, and what you felt, at the point where it seemed to have stalled out.

Initially — and this was after much deliberation and much planning and many meetings — we, in collaboration with our FBI colleagues, had decided that what really made sense was to take the spores that came from the letters that had been recovered and generate DNA sequence information on the 5.2 million letters of the alphabet of the anthrax bacterium and compare those back to the initial stock of material that was acquired in 1981.

The idea was that over the 20 years that the Ames strain had been around, there would be some mutations that would have accumulated in the genetic sequence. Those would be informative and could be useful to make the appropriate links.

In theory, that was a great idea. I don’t think anybody would go back and second-guess that that was a reasonable place to start.

But what we discovered was that when we compared our information at 5.2 million positions for material that came from each of the four letters back to the initial stock, we didn’t find a single difference. There wasn’t a single base pair difference.

I can tell you that was not a meeting I was looking forward to, because at that point, it really seemed like the promise of this relatively new technology had come to a dead end.

You went back to the initial stock that Bruce Ivins then would have had control of. Did you deal with Bruce Ivins on any of this?

We never directly dealt with Bruce Ivins, no. We were dealing with other folks through USAMRIID. CDC was involved. Paul Keim’s lab was involved.

When the FBI took over the investigation very early on, they were really the ones that were running the show, so they were making the connections. They were calling the shots, and they were making the determinations about what material was being sent between labs.

Did you know who Bruce Ivins was?

Of course I knew who Bruce Ivins was, having worked in the biodefense area for a number of years. I had seen him in a number of meetings, but I didn’t consider him to be a close colleague.

… Explain who he was, his reputation, and what your estimations of the man was.

In a sense, he was almost a legend of sorts in the field of weaponization of anthrax, development of an anthrax vaccine. He had been leading a number of key programs at USAMRIID for many years. He was one of the principals in an ongoing, large-scale vaccine trial.

At the same time — and this is just my opinion — he was also eccentric. I don’t mean anything good or bad about that. He was just eccentric. … He wasn’t easy to talk to, more because it seemed like he was uncomfortable with who he was. He just seemed a bit socially awkward. …

A lot of people defined that as “Bruce being Bruce.”

… Not having worked with him, I was not aware of some of the other aspects of his personality that I’ve heard described as being charming, being a bit abrasive at times, being very clever at other times. There seemed to be multiple facets to Bruce’s personality. …

During the initial period of time, … the FBI focused on Dr. [Steven] Hatfill. What were your thoughts about that at the time? …

It was very interesting. During the time that Steve Hatfill was considered the person of interest, my colleagues and I would certainly have some discussions and speculate, “Is this the right person or not?” … We were fascinated by all of this. …

… Explain what took place at USAMRIID and how that was really the next step that you guys worked off of.

I think one of the real breaks in this case, in terms of the molecular genetic component of this, came from an appreciation of basic microbiology.

If you grow a culture of bacteria long enough, certain cells will start to accumulate mutations in DNA sequence, and those mutations can manifest themselves as differences in how the bacteria look when they’re plated out on petri dishes.

Most of the colonies all look to be identical, and they are. They’re essentially identical twins. But then you have these oddballs that may look a little bit different, may grow a little faster or a little bit slower. And the idea is, … they’re the outliers. If you really want to be studying organism X, focus in on the colonies that all look to be the same. That’s a fundamental premise of microbiology.

What happened as part of this investigation, as the different spore preparations were being grown, there was a situation where a plate was left in an incubator a little bit longer than it should have been. And when it was taken out, it was clear that there were some of these same peculiar-looking colonies that had come from the material in the letters.

So one question was, is this just a single spurious event? But through a lot of painstaking work, it was shown that these mutant-type colonies, which we ended up calling morphotypes, could be propagated as you continued to grow the cells through various generations in culture.

All of a sudden, everybody’s attention turned away from the majority of the material that looked to be identical, the identical twins, to really look at the outliers and ask, are the differences in physical properties that we’re seeing on the plate a reflection of some important difference in DNA sequence that our methods would be able to detect?

Why is that important to you? And what do you do about that?

What we were able to do then was to get access to each of these different colony types and go through the process that we had already been through all over again, looking at the genetic code for each of these morphotypes.

This is when, for us, the real breakthrough happened, because we quickly came to see that each of the different morphotypes that had been identified based on certain physical characteristics had underlying and consistent and sustained differences in DNA sequence.

All of a sudden, now we had a molecular marker that could be used to try and trace back to where this material may have come from. …

… If you could somehow match the anthrax that was in the letters to another sample that was pulled in, you’d have a smoking gun. …

Yes. … If we could find molecular differences that held up and could be traced back to a potential source, that would potentially provide the smoking gun and say, “This is where the material came from.”

So the first step in being able to even think about going down that route is finding genetic mutations that are consistent and are reliable.

We were really excited when these mutations and these morphotypes were found in each of the four letters that were recovered as part of the investigation.

So that was another important next step. This wasn’t just a single event or single situation. … This was seen in all four letters, the same mutations, the same morphotypes. …

Was there a conversation where [FBI agent] Scott Stanley comes to you and says: “They’ve found these morphs. Can you guys do something?” …

Absolutely. As soon as the morphotypes had been identified, and the folks at USAMRIID had convinced themselves that these were real — these could be propagated as the material was grown in culture — Scott Stanley from the FBI immediately came back to us and said: “We possibly have a completely new avenue of investigation. You’re going to have to go back to the drawing board. … What do you think about the possibility of generating the same kind of information for all of these morphotypes to see if, in fact, this is where there may be some spelling differences that could be critically important?”

We couldn’t have been more excited at that point in time, because it seemed like this avenue of pursuit was still alive and that we could still likely make an important contribution.

This really was the beginning of basically inventing it from scratch, a new science really?

… The sequencing technologies that we used were not new. They had been around for a while; they had been well validated. … But they were being used in a very different way for this investigation, to try and identify these kinds of changes and do it with the highest possible level of accuracy and confidence, so that this information could ultimately be used for attribution.

What’s the next step? …

It was probably at the end of 2002, a little over a year after all of this broke, that we began our really focused efforts on trying to map the genomes of these [four] different morphotypes. That took us about 18 months.

As we began to get the first information out that identified differences in DNA sequence, it was at that point that the FBI really kicked its efforts to put together the repository of Ames samples into high gear. …

Your role becomes to try to see if you can find a match.

Once we generated this new information from the morphotypes, the first thing we did was go back and compare — at all 5.2 million letters of the genetic code, letter by letter — the sequence in the morphotypes to the sequence from the ancestral strain of Ames that we had worked on starting in the fall or in the winter of 2001-2002.

Fortunately, we have powerful computer algorithms for doing that. … It was through that comparative approach that we were able to identify these mutations, and of course there was great delight.

We found them with one sample. So then we would look and ask, do we see them from a sample from a second letter? From the third letter? From the fourth letter?

That’s when we all of a sudden started to get a lot of yeses instead of nos. It looked like perhaps there was a new way to go about this case that was starting to come together.

Once you know exactly what you’ve got from the letters, and you’ve mapped it, and you compare those to these samples, … what are you finding?

Once we identified the genetic mutations, we spent a fair amount of time developing assays to target in specifically to those regions that differed.

There really wasn’t any sense in going back and looking at all 5.2 million letters of each sample in the repository. We knew where the differences were, so we could focus in very precisely on those regions of the genome.

We developed those assays. Other labs validated those assays. We carried out some of the screening of samples from the repository, but other labs were involved in this as well. …

If this was information that was going to go into a criminal investigation, it would be important to have cross-validation and to have information coming in from different sources and different labs. And hopefully, it would all agree.

What was found?

It was found, in looking at the nearly 1,100 strains in the repository, that there were eight out of the total that contained the four key mutations that had been identified as probably being most important in tracking samples. There were a smaller number that had three, and an even smaller number that contained one or two of these mutations.

That became very important information. It wasn’t as if the majority of the samples in the repository all contained these mutations. It was literally a couple of handfuls of samples, so that allowed the FBI to focus on eight samples instead of 1,100, and ask, how are they related? Are they related? Where did they come from?

What did they find?

What they found in looking at these eight samples that contained all four mutations was that they could all be traced back to a single source flask of Bacillus anthracis spores that had been named RMR-1029 and that had been developed and kept at USAMRIID dating back to either 1997 or 1998.

So what do you all think? … What does this mean?

We clearly all felt that the enormous amount of work and time that had been put in was absolutely worth it.

We all realized, when we began, that the work that we were doing as genetic analysis would never on its own solve the case, but it could provide critically important information to point toward a potential source and at the same time exclude a large number of other potential sources as being where the material came from. …

Why did it take so long?

… Unfortunately, the science … was not something that could be done overnight, and that’s true of science in general. There may be a sense on the part of the public that scientific breakthroughs … happen overnight. They don’t. They can take five, 10, 20 years in initial discovery, follow-up, validation. That all takes time.

Obviously in this situation we wanted to be absolutely certain that the information we had generated was correct.

We got off-track, in a sense, in that we were looking at the wrong part of these cultures initially — the colonies that were all identical. So we had to go back to the drawing board and refocus on the morphotypes. That took time to basically repeat many months of work with a new set of samples.

Then there was all the time involved in putting together the FBI repository, with the FBI developing protocols that labs could use and would follow for submission of their samples: growing all these up; doing quality checks; making sure that everything was as it should be, and then carrying out the screening on nearly 1,100 samples.

As a scientist, I’ve come to accept the fact that a process like this takes time. Unfortunately, there are no shortcuts, and probably in this case, we didn’t want there to be.

Some people have complained that the FBI’s process held things up to some extent; that the inability of scientists to talk to scientists made things difficult. …

… In the beginning, we weren’t operating like a well-oiled machine.

Science, legal investigation, I don’t care what it is, these are all human endeavors. And unfortunately, there can be elements of territoriality, of pride, of not wanting to be completely open, not wanting to trust that your colleagues can do something as well as you can.

I think we’ve learned a lot of lessons from this incident. Probably one of the most important ones is the desire and the need and the value of having open and transparent and seamless communication when it’s necessary. But I know from my own situation in science, that doesn’t always work that way.

There are complaints by some people … that the process was somewhat flawed, that the samples were not taken in a possibly correct fashion, but they were voluntarily given over. As far as the process itself, … did it seem to have problems as far as you saw?

In the middle of all of this, it was unclear whether or not there were major problems in the processes that had been put in place. Some of this only became more clear in retrospect.

Was it perfect? Absolutely not. Is any investigation ever done perfectly? Probably not. I think people did a tremendous job given the complexities of what was going on.

If we could go back to square one and start over, would things be done differently? They’d probably be done differently in every aspect of the investigation. But I still think that things were done with a very high level of competence, with a sincere desire on the part of all the participants to really want to do the best that they could. …

The focus is now on flask 1029. Did you guys pick up pretty quickly what that might mean? When Ivins became the suspect, was it a surprise?

We were really excited that eight of the samples in the repository were able to be traced back to flask 1029. To us, that seemed to be incredibly significant.

At that point, from what we knew, there were perhaps 200 or 300 people at USAMRIID who had potentially had access to that material since the time it had first been put together about four years earlier.

So to me at least, things got much more confused. Even though this flask was presumably in Dr. Ivins’ custody, he wasn’t the only one who went in and out of the flask and had access to it. …

One of the things they were also trying to do is reverse-engineer the actual attack. Explain why that was such a hard thing to do. …

One of the puzzling aspects of the investigation was that there appeared to be two different sources of material. One source that was sent in the letters to New York, to Tom Brokaw and the New York Post, and a second preparation of spores that was sent to Sens. [Tom] Daschle [D-Iowa] and [Patrick] Leahy [D-Vt.].

This notion was based on the fact that the spore preparations physically were very different. They were different in color; they were different in texture. So presumably they didn’t come from the same starting material.

Then that suggested that the material that was sent through the mail didn’t come directly from the 1029 flask. Even if that was the source, then there had to have been a subsequent preparation step to make the material likely twice that was put in the envelopes and sent through the mail.

And there were some peculiar characteristics about these spore preparations. … What kinds of equipment might have been used? Was it the in-your-garage-type equipment or more sophisticated equipment?

There were some efforts to try and reverse-engineer spore preparations, to see if anything that looked like the material that was recovered from the two sets of letters could be generated. But that didn’t work out. …

You’re trying to recreate the weapon before you understand what the weapon is. That would lead to what?

The more you understand what the weapon is, then you might be able to make some assumptions about whether or not this was created in a laboratory setting with all the sophisticated equipment that’s required to do anthrax weaponization. Or perhaps this was done with more rudimentary material in a somewhat more secretive way.

It was never going to be a single key bit of information. But there were so many moving parts, I think, that the FBI was really looking to try and close as many holes and get as much information together as they possibly could. …

… They decided Bruce Ivins is the guy. … Do you believe, from what you’ve seen, what you’ve read, what you know of the investigation itself, that they got it right? …

Ten years after the fact, I’m left probably feeling more frustrated than I had hoped about how all of this came to conclusion. It was obviously a tragedy that this didn’t go to trial because of the Ivins suicide.

But I think that it was also a tragedy because there was so much effort that had gone into trying to put together a set of protocols and a plan for how to carry out this kind of investigation. Basically this was like a dress rehearsal, and we never got an opportunity to do the real production and get feedback.

I think there are still a lot of unanswered questions. I think there are still a lot of holes, and I think the FBI is the first to admit that’s the case.

There is likely some information that might have come out if this had gone to trial that will never see the light of day now that the case has been deemed to be closed. …

I have no way to know whether or not Bruce Ivins was really the perpetrator. I think it’s unfortunate in that there were aspects of his personality that made it very easy to cast him as the eccentric, psychologically disturbed scientist with a possible motive. But that doesn’t mean that he’s guilty. …

What were some of the most worrisome holes that you see, that caused you to pause to some extent?

I think there were holes both in terms of the science and in terms of the more traditional investigation.

In terms of the science, I have absolute confidence in the information that we generated. I absolutely believe that the eight samples that were identified contained the four mutations that were consistent with these samples having been derived from the 1029 flask.

But there is still that doubt. Was it from the 1029 flask or something else? It’s consistent with having come from 1029, but that’s different than saying this material absolutely came from 1029.

There probably should have been some more statistical analysis done, looking to see how frequently these kinds of mutations arise when large preparations of Bacillus anthracis are grown up in fermenters.

That was actually an item that was noted in the National Academy’s report. And I can’t say why that work wasn’t done. …

Then there are all sorts of holes in the more traditional aspect of the investigation: the fact that, as far as I know, there was no information that ever linked Dr. Ivins to the mailboxes in New Jersey at the times that these letters were presumably sent out; the fact that it’s known that there were perhaps 200 or more individuals that had access to this material at any point after this flask, this witch’s brew of spores was created. …

The conclusions for this report, do they surprise you? What do you think the big message from the report is?

I wasn’t at all surprised by the conclusions of National Academy’s report. … There is really nothing that I can take issue with in the report.

I think it points out where the science was strong. It points out where there were still questions that, perhaps, could have and should have been addressed. I think on balance, it was a very good report. …

The biggest conclusion, and the most important conclusion that you think came from it?

Probably the most important conclusion that came from the National Academy’s report was that there probably should have been some additional science done to fill in around the work that we did, to help provide some additional statistical validation to some of these conclusions. …

The other conclusion was that it seemed to be that the FBI had overemphasized how the science defined the end results of the case. Explain that.

This is clearly a matter of interpretation in terms of the comments in the National Academy report.

Was the information overinterpreted? Perhaps it was. But I don’t think there were any fundamental issues with the conclusions. It was just more putting the findings in the context and having statistical data, being able to assess conclusions with a degree of certainty rather than saying absolutely yes or no.

None of these conclusions were going to be black or white. We knew that going into this, and it turned out to be the case coming out.

[Did] the FBI, to some extent, perhaps overemphasize the role of science in proving their case?

I wouldn’t disagree with that statement that they overemphasized the role of science in proving their case. I think the science was some of the strongest evidence that they had, so it’s not surprising that they put a lot of emphasis on that. …

The science was very solid, but the science alone could never provide the answers. So perhaps the FBI did focus a bit too much on the importance of the science to the exclusion of the nonscientific aspects of the investigation.

The [FBI’s] press conference on Aug. 18, 2008 — you were there. … What are you thinking?

… Those of us participating in the press conference arrived at the FBI building a couple of hours before it started. … We all actually signed papers that said we were now no longer bound by our nondisclosure agreements, that we were free to talk about what we knew.

There was a little bit of additional information that came out in some of the discussions, but the whole picture was still not clear.

So it felt a little bit like going in front of a firing squad to walk out into that room full of press for that press conference, knowing not too much more than what we had done, being told that we were now free to talk about all of this. …

Were you surprised at the tone of the FBI as far as how clear they were that Ivins was the man?

I was surprised about their conclusions at that point, but it was based on not having seen so much of the other supporting information that they had been assembling to take this case to trial.

I went into that press conference being very clear that my comments were going to be limited only to the work that we did. I wasn’t going to let myself get pulled down some path into making comments about the potential guilt or innocence of Bruce Ivins, because none of us had been privy to any of that information. …

… What they were saying is, “We’re sure this guy is the guy.” They were stressing science. Did you feel the emphasis they were placing on the evidence that they had gotten from science was somewhat misleading?

I think that the evidence on science probably was misleading.

The science that we had done was above reproach. The interpretation of that science will always be a question that we have to deal with.

Then to go from that to make the link to Bruce Ivins, it all happened so quickly. … So I personally was taken a little bit by surprise by all of this. …

[At] the press conference, what was the mood among the officials from the [Department of Justice] and from the FBI? Was it confident? Was it relieved? Was it anxious because he had killed himself before they could bring it to court?

It was my sense that the mood on the part of the DOJ folks at that press conference was mixed, that they had been taken by surprise by the Ivins suicide. They didn’t necessarily have all of their ducks in a row.

But they went out and put their best face forward, and perhaps that’s why they focused so much on the science, because I think that was probably what all of us were most confident about. …

Did you feel a little sense of awkwardness about being there, because you realized that you were possibly part of a bit of a charade?

… I don’t think I felt that I was there as part of a charade, but I kept reminding myself that I was there representing one very limited aspect of the investigation, and that I couldn’t get caught up in anything beyond that. …

… As a scientist, and knowing how this material has to be dealt with and everything else, do you have questions about the likeliness that somebody like Ivins, despite his knowledge base, could have been involved in this?

… There are days when I think there are just still so many unanswered questions that it is absolutely unfair to place guilt on Ivins. That’s not the way the U.S. system works.

Then there are other days when I think, well, maybe it does make sense. But, what I keep trying to come back to, is … I think we should be doing everything to give him the benefit of the doubt. Because this was not an airtight case, by any means.

I think that for an awful lot of people there is a desire to really want to say that yes, Ivins was the perpetrator; this case can reasonably be closed, and we can put this tragic chapter in U.S. history behind us.

But I think part of what’s driving that is the fact that if he wasn’t the perpetrator, then it means that person is still out there. And that is a truly unnerving thought.

I think it’s even more so in that, in the 10 years since all of this happened, there was such an enormous infusion of federal funding into biodefense research, and so many new facilities were built. There were incentives put in place to try and attract new young talent to start to work on these esoteric but very dangerous pathogens.

So it gets to this whole question of, how concerned should we be about the insider threat? In our desire to try and put additional measures in place to safeguard the U.S. against something like this happening in the future, have we actually just created additional potential monsters? …

One of the other things that people will say — the side that don’t believe that Ivins did it — is: “They didn’t find any spores anywhere. They didn’t find anything on him. They didn’t find anything in his car. They didn’t find anything anywhere in his workplace.” … Is that a question that needs some answers?

I think that the inconsistencies with regard to Ivins, and the fact that no spores were found in his car, you know, the sort of the smoking guns that you would have expected to see if he had been the perpetrator, weren’t there. And yet, on the flip side, you think about all the efforts that had to go into decontaminating the postal facilities, and the volatility of these spores, and the fact that they were around for so long, and they went everywhere — to me, that seems like an enormous inconsistency.

I don’t know what to make of that. That’s an aspect of the investigation that I think represents a big hole and really gives me pause to think about how strong was this case against Dr. Ivins.

… They maintain that he could have grown the stuff; he had the expertise; he could have dried it there at the lab. This question of being able to clean out the equipment, … is that true?

When we get into these kinds of discussions, an awful lot of this really represents healthy skeptical scientific debate with people with opposing views.

But I can tell you, from the work that we do here in the lab — and we work with DNA from a lot of different bacterial organisms — one of our biggest challenges is contamination. It’s DNA that’s left over from the prep that you did previously. … Can we ever get things entirely clean? My sense, the answer is no.

So I would find it surprising that you could take a piece of equipment in which you had grown any bacterial organism, whether it be anthrax or anything else, and get it completely clean, where there was no trace.

Now, does that mean it’s impossible? No. But the amount of time and effort that would likely need to be put in to making that happen would be enormous.

[The NAS report says] they can’t rule out the intentional addition of silicon-based substance. There is a huge debate that is still ongoing about the silicon. What’s your take on that?

I don’t know enough about all that chemistry to even make any sort of credible comments, unfortunately. …

… Is there a reason to continue this debate, or is it all just sort of paranoia?

I think it’s just the nature of those of us who do science to want to engage in debate. And all of these things that we’ve talked about, all of these various aspects of the investigation that still remain under debate probably more than anything illustrate the fact that there was so little known about what to expect when you weaponize a pathogen like anthrax.

These were not large scientific programs that were replicated in labs around the world, so it’s not surprising to me that there are inconsistencies.

But I don’t know that we’ll ever have answers for them, because the only way you put these kinds of things to rest in science is you come up with a hypothesis. You do a set of experiments. You ask, did your results match up with your hypothesis? If not, why not? Go back and do it again.

Just to try and make arguments based on existing information and try and make assumptions about what this must mean or couldn’t possibly mean, without any other effort, to me is just a total waste of time. …

[What about] the thoughts that pressure from the top down, to some extent, perverted the investigation?

There is absolutely a sense that there was so much pressure coming from the top, and from so many different areas, that there almost wasn’t time to really think critically; that everybody was in a reactive mode most of the time, which is not a good thing. …

Does that mean that some mistakes were made? Probably, but not with any malicious intent. I don’t think they were ever made with the intent to not get at the truth.

It was always a scramble, and everybody was always reacting to a need for information yesterday rather than tomorrow. Tomorrow was always too late. …

More Stories

Kherson After Liberation: Co-producer of ‘Putin’s Attack on Ukraine’ Documentary Describes Visit
A Ukrainian filmmaker and journalist who was on one of the first trains traveling to the newly liberated city talks to FRONTLINE about the damage he saw in Kherson after eight months of Russian occupation.
November 29, 2022
As Donald Trump Announces His 2024 Run, a Look Back at His Presidency and Impact
FRONTLINE has built a unique public record, in documentary format, of the former president’s impact on American life, politics and democracy — and his previous battles with a special counsel and the Department of Justice.
November 16, 2022
How American Politics Reached This Fraught Moment: 12 Documentaries to Watch Ahead of the Midterms
As a divided America prepares to vote and fears of political violence continue, these FRONTLINE documentaries show how U.S. politics reached this moment.
November 4, 2022
How Russian Soldiers Ran a "Cleansing" Operation in Bucha
"I’ve already killed so many civilians,” a Russian soldier told his wife from Bucha, Ukraine. The Associated Press and FRONTLINE obtained hundreds of hours of CCTV footage and intercepts of audio calls by Russian soldiers that show for the first time what a Russian "cleansing" operation looked like.
November 3, 2022