A day after the Justice Department released hundreds of documents purporting to link Bruce E. Ivins to the 2001 anthrax killings, scientists and legal experts criticized the strength of the case and cast doubt on whether it could have succeeded.
Federal investigators presented a raft of circumstantial evidence this week intended to prove Ivins' guilt beyond a reasonable doubt. But officials lacked direct evidence, such as hair fibers, DNA samples or handwriting analysis, that the eccentric microbiologist created the deadly powder in his Fort Detrick lab. Questions also remain about Ivins' ability to convert the spores stored in his lab into the powder sent through the mail.
More than half a dozen experts in law and bioterrorism pointed out yesterday what they consider major flaws in the government's case and said they were not convinced that Ivins acted alone in mailing the letters that killed five people - or that he was involved at all. They said that the science that led the FBI to Ivins has not been explained and that the other evidence did not amount to conclusive proof.
Because Ivins committed suicide last week, that evidence will never be tested at trial, but his attorney has repeatedly insisted that the scientist was innocent.
The FBI said it used a sophisticated mapping technique to connect the anthrax in the letters with a flask in a Fort Detrick lab where Ivins worked. But that technique is so new that in the hands of a skilled defense lawyer, it could be "unraveled in front of a jury," said Michael Greenberger, a professor at the University of Maryland Law School.
Not all legal experts were skeptical of the case. Former federal prosecutor E. Lawrence Barcella said the FBI appeared to have done a remarkably thorough investigation. "They've made a very strong circumstantial case, an extremely strong circumstantial case," Barcella said.
Others said the focus on Ivins' lab raised concerns. The government said that 16 government, commercial and university labs had the strain of anthrax with the same genetic mutations as the anthrax used in the attacks. Only one of those 16 was in Maryland or Virginia - where the government thinks the envelopes used in the attacks were purchased. That lab is the one where Ivins worked.
"I thought that was a bit of a stretch," said Jonathan D. Tucker, a biological warfare expert on a federal commission to prevent terrorism and the spread of weapons of mass destruction. "It's such a key piece of their argument, and it's based on inference. We don't know which other labs had the strains with the mutations."
