The US army bio-weapons scientist who killed himself this week, Bruce E. Ivins, had been under suspicion by some FBI agents since early 2002 when anthrax spores were found near his desk, but FBI supervisors were more focused then on another scientist, Steven Hatfill, and dismissed concerns about Ivins, federal law enforcement sources tell ABC News.
Instead, Ivins became deeply involved in the FBI anthrax investigation, helping to analyze the anthrax-laden letters sent to members of Congress and participating in strategy meetings about how to find the person responsible.
Ivins took his life earlier this week after, The Los Angeles Times first reported today, his lawyers were told by federal prosecutors that Ivins would soon be charged with the 2001 anthrax mailings that killed five people and panicked the nation.
The FBI and the Department of Justice have, so far, declined to comment on Ivins or his role in the massive investigation.
"If he in fact was the correct person, he was actually put in charge of analyzing the evidence of his own crime," said ABC News consultant Brad Garrett, a former FBI agent who worked on the anthrax case until his retirement from the bureau last year.
"All of the scientists there who worked with us were supposed to have been investigated and given polygraph tests," Garrett said.
One of Ivins' colleagues confirmed that Ivins had been under suspicion for years and had long ago hired a criminal defense lawyer.
More recently, the FBI carried out search warrants of Ivins' home, office and research space as part of a renewed investigation, according to federal law enforcement sources.
Ivins' attorney, Paul Kemp, released a statement today saying that his client had fully-cooperated with the government's investigation and assisted them in any way he could.
"We assert his innocence in these killings, and would have established that at trial," said Kemp. "The relentless pressure of accusation and innuendo takes its toll in different ways on different people, as has already been seen in this investigation. In Dr. Ivins' case, it led to his untimely death."
Ivins, 62, worked at the U.S. Army Medical Research Institute of Infectious Diseases at Fort Detrick, Md.
Friends there say he was well known to be susceptible to deep depression and was concerned he would be falsely linked to the anthrax attacks.
"They took an innocent man, a distinguished scientist, and smeared his reputation, dishonored him, questioned his children and drove him to take his life," said one outraged colleague, who asked that his named not be used for fear "the FBI will come after me."
"He just didn't have the swagger, the ego to pull off that kind of thing, and he didn't have the lab skills to make the fine powder anthrax that was used in the letters," said the colleague, a scientist who also works at the US Army facility at Ft. Detrick.
Federal agents first became suspicious about Ivins in early 2002 when they learned that he had failed to report anthrax had been found near his desk, away from the laboratory area where he worked with anthrax as part of the team formulating a new anthrax vaccine now awaiting FDA approval.
According to a subsequent Army report, one of his office mates raised the issue of contamination in December 2001 and Ivins took it upon himself to investigate, swabbing the area and decontaminating it.
But after confirming the presence of anthrax, law enforcement officials say, Ivins delayed filing a report for three months, in violation of Army protocols.
Ivins reportedly said he took the action because he did not want to cause an uproar.
The renewed focus on Ivins came after the FBI concluded it had been too single-minded in its focus on Hatfill. The Department of Justice agreed in June to a $5.8 million settlement with Hatfill over a lawsuit alleging the government had invaded his privacy and violated his rights.
Until, or unless, the FBI makes public its case against Ivins, his suicide is certain to raise similar questions.
"Could this be another single-minded focus, is this another we think we got him but we don't have him," asked former FBI agent Garrett.
"Is this going to be Hatfill-2?"