So who actually mailed the anthrax letters? In the first part of the investigation, the government focused its attention on bacteriologist Dr. Steven Hatfill. But, eventually, the FBI admitted that Dr. Hatfill was not involved at all, publicly exonerated him, and paid him almost five million dollars in damages for illegally leaking his name to the press.

Next, the task force unequivocally declared that deceased government virologist and anthrax specialist Dr. Bruce Ivins was the perpetrator. Based on genetic testing of the anthrax spores in the letters, the government concluded that the only possible source for the spores was Dr. Ivins's lab.

This post contains the first part of Chapter 3 of Anthrax to Zodiac where we examine the details of the accusation and exoneration of Dr. Hatfill and the early part of the investigation into Dr. Ivins.

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