The
National Research Council committee scheduled a briefing in Washington on its
170-page report, which examines the novel microbial forensic techniques used by
the FBI to determine that Bruce Ivins acted alone in making and sending the
powdered spores.
“We find
the scientific evidence to be consistent with their conclusions but not as
definitive as stated,” said Lehigh University President Alice P. Gast, who
chaired the 16-member panel.
The FBI
said in a written statement that its conclusions were based on a traditional
investigation as well as scientific findings. The agency said the science
provided leads but that science alone rarely solves cases.
“The FBI
has long maintained that while science played a significant role, it was the
totality of the investigative process that determined the outcome of the
anthrax case,” the agency said.
Gast
declined to comment on the guilt or innocence of Ivins, who died of an
apparently intentional Tylenol overdose in 2008 as the US Justice Department
prepared to indict him for the attacks. He had denied involvement, and his
lawyer and some colleagues have maintained he was an innocent man hounded to
self-destruction.
Early
last year, the FBI formally closed its investigation into the anthrax letters
that unnerved a nation still reeling from the Sept. 11, 2001 terrorist attacks,
saying it had concluded that Ivins planned and executed the mailings by
himself.
Five
people died in October and November 2001 from anthrax inhalation or exposure
linked to the letters. They were a Florida photo editor, two postal workers in
Washington, a hospital employee in New York City and a 94-year-old woman in
Connecticut. Seventeen others were sickened.
Postal facilities,
US Capitol buildings and private offices were shut for inspection and cleaning
by workers in hazardous materials suits from Florida to New York and elsewhere.
Investigators
have acknowledged that the case against Ivins, who worked at Fort Detrick in
Frederick, is circumstantial. Still, Jeff Taylor, the United States Attorney
for the District of Columbia, said in 2008 that prosecutors could prove to a
jury beyond a reasonable doubt that Ivins was responsible for the attacks.
The FBI
asked the congressionally chartered council to validate its use of new and
emerging science in the investigation.
The panel
said the science didn’t support the Justice Department’s statement in a 2010
report that “the anthrax mailer must have possessed significant technical
skill,” an assertion that narrowed who could have been responsible.
Various
experts told the panel it could have taken anywhere from two days to several
months to prepare the spores.
“Given
uncertainty about the methods used for preparation of the spore material, the
committee could reach no significant conclusions regarding the skill set of the
perpetrator,” the report states.
The
report also challenges investigators’ conclusion that the parent material of
the Ames anthrax spores used in the attacks came from a flask labeled RMR-1029
that was created and solely maintained by Ivins.
“The
scientific link between the letter material and flask number RMR-1029 is not as
conclusive as stated” by the Justice Department, the report says. The committee
and investigators agreed, though, that spores from the flask would have
required one or more intermediary growth steps to become the material in the
letters.
The
report reveals that the FBI pursued a possible Al-Qaeda link to the mailings by
trying without success to grow anthrax from swabs and swipes taken from an
unspecified overseas site at which a terrorist group’s anthrax program was
allegedly located. The samples had tested positive for Ames anthrax — false
positives aren’t unusual — but wouldn’t grow spores, according to sketchy
information in a newly declassified document that the FBI gave the committee
December or January.
The
committee said the methods used in the inconclusive tests should be explored in
more detail.
