Despite demons, Ivins stayed on at biolab

Separately on Thursday, the FBI said in an affidavit that computers recently seized from a Frederick, Md., library may hold clues about Ivins and the mailings.

Ivins used the computers for about 90 minutes on July 24 to read e-mail and review a Web site dedicated to the anthrax investigation, Special Agent Marlo Arredondo wrote in the seven-page document. Ivins went to the library on the day he was released from a two-week psychiatric hospital stay that followed his counselor's petition for a protective order — and just a few days before he took his own life.

At most labs, unless scientists have been committed to a mental hospital, psychiatric issues don't factor into the security process. That's a policy decision that balances security and privacy rights.

As for why the Justice Department didn't arrest Ivins in 2005 — for lying to investigators, for instance — U.S. Attorney Jeffrey Taylor said Wednesday that authorities were still building their primary anthrax case at that time.

"At that point, the investigation still had a long way to go," Taylor said, "because there's still a universe of people who might have access to that flask, or people with whom Dr. Ivins may have shared some portion of that anthrax."

An arrest for lying might have barred Ivins from the lab, but it almost certainly wouldn't have taken him off the street. And it could have torpedoed any chance to continue building the anthrax case.

Taylor was asked how such a troubled man could have gotten away with the attacks for so long.

"Well, I'm not going to speculate on how. I can't get into his mind," Taylor replied. "I think what you're asking, sir, answers the question itself. He had been this way for a number of years, going back for quite a number of years, and was still able to carry on his professional life at USAMRIID."

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