WASHINGTON — After four years pursuing one former Army scientist on a costly false trail, F.B.I. agents investigating the deadly anthrax letters of 2001 finally zeroed in last year on a different suspect: another Army scientist from the same biodefense research center at Fort Detrick in Frederick, Md.

Over the last 18 months, even as the government battled a lawsuit filed by the first scientist, Steven J. Hatfill, investigators built a case against the second one, Bruce E. Ivins, a highly respected microbiologist who had worked for many years to design a better anthrax vaccine.

Last weekend, after learning that federal prosecutors were preparing to indict him on murder charges, Dr. Ivins, a 62-year-old father of two, took an overdose of Tylenol with codeine. He died in a Frederick hospital on Tuesday, leaving behind a grieving family and uncertainty about whether the anthrax mystery had finally been solved.

The apparent suicide of Dr. Ivins, a Red Cross volunteer and amateur juggler who had won the Defense Department’s highest civilian award in 2003, was a dramatic turn in one of the largest criminal investigations in the nation’s history. The attack, the only major act of bioterrorism on American soil, came in the jittery aftermath of the Sept. 11 attacks. It killed five people, sickened 17 others and set off a wave of panic.

In the early days after the letter attacks, in September and October 2001, Dr. Ivins joined about 90 of his colleagues at the Army Medical Research Institute of Infectious Diseases in a round-the-clock laboratory push to test thousands of samples of suspect powder to see if they were anthrax. Later, in April 2002, he came under scrutiny in an Army investigation of a leak of potentially deadly anthrax spores outside a sealed-off lab at Fort Detrick. He later admitted he had discovered the leak but not reported it.

Whether the focus on Dr. Ivins had resolved the case of the anthrax letters was unclear. A federal law enforcement official said that Dr. Ivins had been regarded as a strong suspect and that agents had been nearing an arrest, and a lawyer familiar with the investigation said he believed that prosecutors had planned to charge only Dr. Ivins. The link between Dr. Ivins’s suicide and the federal investigation was first reported on Friday in The Los Angeles Times.

But the Federal Bureau of Investigation declined on Friday to make public its case against Dr. Ivins, noting that evidence was under court seal as part of a grand jury investigation. Officials said they were briefing the victims of the anthrax letters — those who recovered, as well as family members of those who died — and would need to go to court to have evidence unsealed before it could even be summarized for the public.

A lawyer who had represented Dr. Ivins since May 2007, Paul F. Kemp, insisted that Dr. Ivins was innocent and had been driven to suicide by false suspicions.

“For six years, Dr. Ivins fully cooperated with that investigation, assisting the government in every way that was asked of him,” Mr. Kemp said in a written statement, calling the microbiologist “a world-renowned and highly decorated scientist who served his country for over 33 years with the Department of the Army.”

“We assert his innocence in these killings and would have established that at trial,” Mr. Kemp said. “The relentless pressure of accusation and innuendo takes its toll in different ways on different people, as has already been seen in this investigation.”

Mr. Kemp was clearly referring to the case of Dr. Hatfill, who was the focus of intensive F.B.I. and news media attention in the case beginning in mid-2002 and received a $4.6 million settlement from the government in June to settle a lawsuit accusing the F.B.I. and the Justice Department of destroying his career and personal life with leaks.

Whatever the cause of his suicide, Dr. Ivins had been behaving bizarrely in the weeks before his death. He was hospitalized briefly for depression and, according to a complaint filed with the police, threatened to kill a social worker who had treated him in group therapy, among others, in rants referring to his expectation that he would be charged with five counts of capital murder.

Read the complete story in www.nytimes.com

Source
www.nytimes.com

By SCOTT SHANE and ERIC LICHTBLAU
Published: August 2, 2008