New doubt on a pillar of anthrax-letter cases

WASHINGTON - The Justice Department has called into question a key part of the FBI's case against Bruce Ivins, the Army scientist accused of mailing the anthrax-laced letters that killed five people and terrorized Congress a decade ago.

Shortly after Ivins committed suicide in 2008, federal investigators announced that they had identified him as the mass murderer who sent the letters to members of Congress and news-media outlets. The case was circumstantial, with federal officials arguing that Ivins had the means, motive, and opportunity to make the deadly powder at the U.S. Army Medical Research Institute of Infectious Diseases at Fort Detrick, Md.

Now, however, Justice Department lawyers have acknowledged in court papers that the sealed area in Ivins' lab - the so-called hot suite - did not contain the equipment needed to turn liquid anthrax into the refined powder that floated through congressional buildings and post offices in the fall of 2001.

The government said it continued to believe that Ivins was "more likely than not" the killer. But the filing in a Florida court did not explain where or how Ivins could have made the powder, saying only that his secure lab "did not have the specialized equipment ... that would be required to prepare the dried spore preparations that were used in the letters."

The government's statements deepen the questions about the case against Ivins, 62, who killed himself before he was charged with a crime. Searches of his car and home in 2007 found no anthrax spores, and the FBI's eight-year, $100 million investigation never provided direct evidence that he mailed the letters or identified another location where he might have secretly dried the anthrax into an easily inhaled powder.

Earlier this year, a report by the National Academy of Sciences questioned the genetic analysis that had linked a flask of anthrax stored in Ivins' office to the anthrax in the letters.

The court papers were uncovered by a reporter for PBS's Frontline, which is working on a documentary on the case with McClatchy Newspapers and ProPublica, an investigative newsroom.