Questions remain over anthrax case

Various : The FBI has released details about its case against accused researcher Bruce Ivins, who killed himself last week after being told he would be prosecuted as the prime suspect in the 2001 anthrax attacks. A number of websites have provided some analysis of the FBI’s case. The Smoking Gun has collated the highlights to the prosecution’s case . Meryl Nass, a noted anthrax researcher, writes on her blog Anthrax Vaccine that “What came out today was another pastiche of innuendo and circumstantial evidence, with an awful lot of holes.”

Nass raises the following main questions:

1. Ivins had just been immunized against anthrax. He was required to have yearly immunizations, and some anthrax scientists have chosen to be vaccinated every six months for safety, since the vaccine’s efficacy is weak -- and Ivins had proven its weakness in several animal models. In his career he had probably received about 33 separate anthrax vaccinations.

2. Earlier in the week, anonymous officials at the FBI leaked to the press that the envelopes came from the specific post office he frequented. Today the affidavit states it is “reasonable to conclude” they were purchased in Maryland or Virginia.

3. Choosing a strain that would direct suspicion at Ivins. The perpetrator(s) were tremendously careful to leave no clues vis a vis the envelopes. For example, block lettering was used, which is the hardest to identify with handwriting analysis. Second, stamped envelopes were chosen to avoid using saliva. Third, there were no fingerprints on anything.

Why would the person(s) who took such care select an anthrax strain that would focus suspicion on himself? In 2001, strain analysis was possible. It had been discussed many times as a forensic tool for biowarfare, including in a paper Nass wrote in 1992 , which Ivins had read, and in which Nass thanked him for his contributions.

4. Ivins was the “sole custodian” of the strain. But the strain was grown in 1997, and more than 100 people had access to it over that four year period. Having received a sample, or obtained it surreptitiously, they would be “custodians” of it too.

Nass also points out that the FBI report does not explain how the anthrax was weaponized, nor can explain how Ivins created it. The FBI also cannot explain how the letters were mailed from Princeton. “Either Ivins had an alibi or he didn’t.... If Ivins cannot be placed in New Jersey on those dates, he is not the attacker, or he did not act alone,” says Nass.

Update: 8/19/2008. The FBI release some of the evidence related to their investigation. NPR’s David Kestenbaum provides some details of the case, along with New York Times reporters Eric Lichtblau and Nicholas Wade . Although some of the techniques have been reviewed, the research has yet to be independently verified by experts not associated to the case. Richard O. Spertzel, a retired microbiologist who led the United Nations’ biological weapons inspections of Iraq, told the New York Times that he remained skeptical of the bureau’s argument despite the new evidence. “It’s a pretty tenuous argument,” Spertzel said, adding that he questioned the bureau’s claim that the powder was less than military grade. Nass adds some more questions to the coverage