Harp learned that this investigation would not follow FBI procedures for strict confidentiality. For starters, Mueller instructed him to brief Daschle and Sen. Patrick Leahy (D-Vt.), chairman of the Judiciary Committee. Each had been intended recipients of anthrax letters.
FBI officials wanted to assure the senators that the bureau was "very aggressively investigating the case," Harp testified. Nevertheless, sharing confidential investigative information was, he said, "an unusual step."
By the end of October, two Washington-area postal employees had died. In New York, a hospital supply worker also succumbed. On Nov. 21, 2001, the fifth anthrax victim, a woman in Oxford, Conn., died.
Federal investigators began looking into scientists who had worked with biological agents. Hatfill was one of those contacted for an FBI interview. His name also was floated within the gossipy networks of the scientific community. Some academics speculated that the mailings were the work of an American who sent the anthrax to boost research funding.
The FBI organized three teams of specialists, based in Washington, D.C., and in Frederick, Md., near where Hatfill lived and worked. Other agents and postal inspectors were deployed in Florida, New Jersey and elsewhere.
But external pressures were outpacing the investigation.
On Jan. 4, 2002, New York Times columnist Nicholas D. Kristof began goading the FBI. "I think I know who sent out the anthrax last fall," he wrote, describing the unnamed suspect as "an American insider, a man working in the military bio-weapons field."
On May 24, Kristof called for lighting "a fire under the FBI" and described the suspected American insider in more detail. Later, the columnist wrote that he was referring to Hatfill.
Hatfill's background invited questions.
Raised in central Illinois, he attended college in Kansas before serving in the Army. He earned a medical degree at the University of Zimbabwe and practiced medicine in South Africa. From 1997 to 1999, Hatfill was a virology researcher in the Army's labs at Ft. Detrick, Md., specializing in ways to prevent or treat infection from such lethal pathogens as the Ebola and Marburg viruses.
In a search of Hatfill's apartment, investigators found an unpublished novel he had written in which a wheelchair-bound man attacks Congress using plague bacteria.
Yet no physical evidence or witness account emerged to show that Hatfill had ever handled or possessed anthrax or that he had a role in mailing it.
