Some of the "evidence" against him was awfully shaky. For instance, the FBI released emails in 2008 in which Ivins describes being treated for mental problems--nevermind the fact that anyone hounded by the FBI the way he was might develop some mental problems. Another piece of "evidence" is that he was working late laboratory hours. Oh, heaven forbid that a scientist work late in the lab, it MUST be a sign that they're up to no good (says sarcastically the person who, as a grad student, often worked til 10 pm or later, and came in on weekends and holidays as well).
I’m a scientist. I looked right past those bits of the FBI report without even considering them. :-)
Actually, on Monday at a seminar in Washington that is the subject of this thread, someone who worked at Ft. Detrick with Ivins, Dr. John Ezzell, said it was possible that Ivins was the anthrax mailer.
And according to Dina Temple-Raston, an NPR reporter who lectures on the case, "All his co-workers think Ivins did it.