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Closing the Anthrax Investigation

Anthrax Investigation
Closing a Chapter


Joseph Persichini (center), Assistant Director in Charge of the FBI's Washington Field Office, with U.S. Attorney Jeff Taylor (left), District of Columbia, and Chief Postal Inspector Alexander Lazaroff of the U.S. Postal Service, explains recent developments in the government's Amerithrax case.

Joseph Persichini (center), Assistant Director in Charge of the FBI’s Washington Field Office, with U.S. Attorney Jeff Taylor (left), District of Columbia, and Chief Postal Inspector Alexander Lazaroff of the U.S. Postal Service, explains recent developments in the government’s Amerithrax case.

The victims and family members of the 2001 anthrax mailings have waited patiently for nearly seven years to find out who was responsible for the worst case of bioterrorism in U.S. history. This morning during a special briefing at FBI Headquarters, Director Robert Mueller provided answers. The briefing took place several hours before the public release of documents relating to the investigation.

While updating victims and their families on the case—in which five people were killed and 17 were sickened—Mueller said that “the pain and suffering the attacks caused the victims and their families was in the minds of all the investigators” as they tirelessly worked to solve the case. That pain and suffering, he added, “has never, ever been lost to us.”

Read: Court records related to Amerithrax case

This afternoon during a press conference, Department of Justice and FBI officials highlighted some of the information contained in the just-released Amerithrax documents, explaining why charges were about to be brought against anthrax researcher Dr. Bruce Ivins, who took his own life before those charges could be filed.

U.S. Attorney Jeff Taylor, District of Columbia, said that normally evidence against a suspect who has not been charged is not publicly released, in part because of the presumption of innocence. “But,” added Taylor, “because of the extraordinary public interest in this investigation...we are compelled to take the extraordinary step of providing the victims, their families, Congress, and the American public with an overview of some recent developments as well as some of our conclusions.”

Because of Ivins’ death, the government will not be able to present its case in court. But according to Assistant Director in Charge Joseph Persichini, FBI Washington Field Office, “Bruce Ivins was responsible for the death, sickness, and fear brought to our country by the 2001 anthrax mailings.”

The Amerithrax investigation is one of the largest and most complex investigations ever conducted by law enforcement. The Amerithrax Task Force, comprised of 17 special agents and 10 U.S. postal inspectors, has conducted more than 9,100 interviews, executed more than 70 searches, and followed leads across six continents. Along the way, a brand new science was developed that ultimately led to the big break in the case.

That science—creating a DNA equivalent of a fingerprint—allowed investigators to pinpoint the origins of the anthrax. The FBI Laboratory, in conjunction with the best experts in the scientific community, developed four highly sensitive and specific tests to detect the unique qualities of the anthrax used in the 2001 attacks. This took several years to accomplish, but in early 2005 the groundbreaking research successfully identified where the anthrax used in the mailings had come from.

Another key piece of evidence was provided when investigators were able to identify a limited geographic area where the anthrax envelopes were purchased based on a forensic investigation that revealed printing defects in certain batches of envelopes.

In 2006, speaking about the investigation, Persichini said investigators were frustrated that no arrests had been made, but that “no one in the FBI has, for a moment, stopped thinking about the innocent victims of these attacks...The FBI’s commitment to solving this case is undiminished.”

Today, Persichini was able to tell the American public that a chapter on one of the most heinous crimes committed against the citizens of the United States has been closed.

Amerithrax Investigation
- FBI Records on the Amerithrax Case
- Linguistic and Behavioral Analysis (2001)
- The Search for Anthrax
- Details and Images of Letter to Sen. Patrick Leahy