The FBI claims that Dr. Ivins drove to Princeton, New Jersey during the evening of September 17th to mail the anthrax letters, and the fact that his whereabouts cannot be confirmed show that he is guilty.
However, as a 2002 article from Princeton University’s The Daily Princetonian points out:
“The box in which spores were found was used to store sorted incoming mail and outbound letters, leading some to speculate that a letter addressed to an area resident might have picked up spores on contaminated sorting equipment before arriving in Princeton.”
As confirmed in an August 14, 2002 article in the The Times of Trenton:
“The box had two purposes: It was used by the public to drop off mail and was used by the Postal Service to hold sorted mail for letter carriers to deliver.”
Because the mailbox was used to store mail previously deposited in various locations in the area, it is possible that the letters were actually mailed days before September 17th, when Ivins’ whereabouts were accounted for.
Moreover, if the spores in the Princeton mailbox came from cross-contamination, the anthrax may have originated somewhere entirely different.
Hat tip to Old Atlantic Lighthouse.