Ever since they officially wrapped up their investigation into the anthrax attacks, Justice Department and FBI officials have admitted that their case against Bruce Ivins wasn’t exactly air tight. There was more than enough circumstantial evidence to prove Ivins’ guilt, they said. But they could never quite figure out where, when, or how the Army biodefense researcher brewed up or dried the lethal spores that wound up killing five people in 2001. “We still have a difficult time nailing down the time frame,” special agent Edward Montooth, who headed up the anthrax investigation, told me. “We don’t know when he made or dried the spores.”

Yesterday, however, the Justice Department’s civil division, locked in a lawsuit with the original anthrax victim’s family, appeared to take that argument about fifty steps further. In a court filing, the lawyers said Ivins’ former workplace, the United States Army Medical Research Institute for Infectious Diseases, didn’t stock the gear in its hot suites needed to create the lethal spores. Ivins’ ability to make the deadly anthrax wasn’t unclear; it was impossible. “USAMRIID did not have the specialized equipment in a containment laboratory that would be required to prepare the dried spore preparations that were used in the letters,” wrote Tony West and his civil division colleagues. (The filings were first reported by ProPublica, Frontline, and McClatchy.)

Small problem: that conflicted with the known facts of the case, the national security division’s reading of those facts.

It’s just the latest public faceplant in a case that’s already seen way too many — from “persons of interest” wrongly harassed to key evidence accidentally destroyed.

So today, under pressure from his Justice Department colleagues, West and friends quickly walked back those statements — and tried to remove a few toes from their collective mouth, if they couldn’t manage the whole foot.

In fact, “USAMRIID had equipment that could be used to dry liquid anthrax in the same building where anthrax research was conducted,” the civil division wrote today in a “notice of errata.”

Ivins’ particular hot suite, B3, didn’t have a freeze-drying machine called a lyophilizer. But there was one elsewhere in the building. And besides, there are other gadgets that can dry spores — ones that Ivins had around.

Were those “speedvac” drying machines heavy-duty enough to make the killer spores? Ivins’ colleagues and friends have long said they were not.

In a deposition, USAMRIID scientist Pat Worsham said, “I don’t believe that we had facilities at USAMRIID to make that kind of preparation. It would have taken a great deal of time; it would have taken a huge number of cultures; it would have taken a lot of resources that would have been obvious to other people within containment when they wanted to use those resources.

That statement is significant, not only because Worsham was an world-renowned anthrax authority. She was also the person whose work eventually lead to the most rock-solid evidence against Ivins: a flask under his control with major genetic similarities to the lethal spores. Without Worsham, the FBI wouldn’t have even had a circumstantial case against Ivins.

Does that still leave the possibility that Ivins drew his spores elsewhere? It does. Could Worsham be mistaken? She could. But at the very least, Worsham’s statement (and the civil division’s errata) mean that this case will continue to linger, 10 years after the attacks that spawned it.

Photo: DOJ