WASHINGTON - Despite the Justice Department's pronouncement that government microbiologist Bruce Ivins unleashed the 2001 anthrax attacks that killed five people, three key questions about the case remain unanswered:
• Can the FBI prove that a flask of anthrax in Ivins' laboratory at Fort Detrick, Md., contained the same mutated strain of powder that was in the envelopes mailed to two U.S. senators?
• Did Ivins, who committed suicide last week, have the technical capability to produce that form of anthrax?
• Why, after he came under suspicion in 2005 or earlier, was Ivins allowed to continue working in the bioweapons laboratory at Fort Detrick?
As federal prosecutors and FBI agents moved to close the seven-year investigation, former employees at the U.S. Army Medical Research Institute of Infectious Diseases and other biological weapons experts Thursday expressed skepticism about the case that has been presented publicly.
The FBI said Wednesday that it had winnowed eight samples that contained all four of the genetic mutations in the anthrax-laced letters out of 1,000 anthrax samples from 16 laboratories and traced all eight to a batch in Ivins' lab that had the same "DNA fingerprint."
However, Jeffrey Adamovicz, who directed the bacteriology division at Fort Detrick in 2003 and 2004, said the FBI trail is "a little disturbing" because it relies on a common contaminant in laboratories and in the environment. While the FBI said it found a unique mutation of that contaminant, Adamovicz said, it has yet to say that this strain "was found in Dr. Ivins' lab and no one else's."
Donald Henderson, a scholar at the University of Pittsburgh's Center for Biosecurity who assisted the government investigation, said the FBI's case against Ivins "just doesn't add up." He said the FBI must produce its DNA evidence for scrutiny by scientists.