“If the case is solved, why isn’t it solved?” Mr. Grassley asked. “It’s all very suspicious, and you wonder whether or not the F.B.I. doesn’t have something to cover up and that they don’t want to come clean.”The story also mentions several boxes of material Ivins had kept in relation to the case:
A government lawyer not involved in the investigation will soon review the papers with Mr. Kemp, who said some might be given to investigators or made public.It's hard to imagine Ivins would have kept anything in those files to completely exonerate himself otherwise his lawyer would already have them. They may tend towards incriminating him, which if true could close the case for all but the wackiest of conspiracy theorists. We'll see. Maybe.
Meanwhile, I've spent some time perusing the transcript of the August 18 briefing held by FBI featuring some of their lab scientists and other scientists who worked on the case speaking with members of the press. My thoughts are stashed at this new continuation site, for those who give a rip.