Sep 16, 2008 (CIDRAP News) – The FBI plans to ask the National Academy of Sciences to review the bureau's investigation that led to its conclusion that government microbiologist Bruce E. Ivins committed the 2001 anthrax attacks, FBI Director Robert Mueller III told Congress today.
Mueller's revelation before the House Judiciary Committee comes in the wake of doubts expressed by a number of scientists about the FBI's findings and calls from several experts for an independent review of the bureau's work in the case.
In an opening statement before the committee hearing, which was webcast, Mueller said the FBI has "initiated discussion with the National Academy of Sciences" about a review of the investigation.
Later, in response to questions from Rep. Jerrold Nadler, D-N.Y., Mueller said, "As I indicated, we're in discussion with and are going to request the National Academy of Sciences to review the work that was done in the course of this investigation."
Ivins died in an apparent suicide Jul 29 as the FBI was preparing to charge him in the attacks, in which anthrax-laced letters mailed to two US senators and several media offices led to 22 illness cases, 5 of them fatal. Ivins had worked at the US Army Medical Research Institute of Infectious Diseases (USAMRIID) for many years and had done research on anthrax vaccines.
The FBI announced on Aug 6 its conclusion that Ivins was to blame. The evidence cited was largely circumstantial, but the agency said scientists had developed a new DNA fingerprinting technique that enabled them to match the mailed anthrax to a batch of anthrax that was in Ivins' custody at USAMRIID.
Since then, a number of disease and biodefense experts have said it is not possible to judge the FBI's claim about the genetic match without seeing the full scientific details, which have not been released. In addition, a number of observers have raised questions about other aspects of the case, such as how the FBI eliminated a large number of other USAMRIID workers who had access to the anthrax in Ivins' work area.
Another question is whether the anthrax powder used in the attacks was a simple preparation of dried anthrax spores or a special weaponized preparation. Early in the investigation, the FBI suggested that the spores were specially treated to make them spread more easily through the air and into the lungs, implying that it would have been difficult for one person to produce them. But at an Aug 18 press conference, FBI experts said they had determined that making the anthrax was a fairly simple process. They said that silica found in the powder occurred naturally, not as a special additive.
Nadler brought up this issue at today's hearing. Citing a report that silica content higher than 1% in the anthrax would not occur naturally, he asked Mueller, "What was the percent of silica?"
"I'd have to get back to you on that," Mueller replied.
"If the percent is greater than 1%, it would indicate the anthrax was manipulated," Nadler said. He said only a "handful" of laboratories could achieve that, and asked Mueller if the FBI had investigated all of those labs and how it ruled them out.
"You can assume we looked at every lab in the US and several overseas" that had people and facilities capable of preparing the anthrax powder, Mueller said. But he said would have to get back to Nadler later about how the bureau cleared individual labs of suspicion.
The anthrax probe was just one of several topics covered in the committee hearing. Early in the session, Committee Chairman John Conyers, D-Mich., castigated Mueller for not responding directly to questions the committee had sent to him in advance.
"How come we can't get some straight answers on the questions I wrote you and I asked you in person? What is this?" Conyers asked after Mueller's opening statement.
Mueller said the bureau's responses to the committee questions had to be reviewed by the Justice Department, causing inevitable delays. "I do believe we've tried to be responsive. I do believe we've been responsive to those questions," Mueller said.
Mueller is scheduled to testify before the Senate Judiciary Committee tomorrow.
Sep 9 CIDRAP News story "Congress seeks answers from FBI in anthrax case"
Aug 20 CIDRAP News story "FBI says it easily replicated anthrax used in attacks"
House Judiciary Committee site