It was the biggest manhunt in FBI history. So it’s not surprising that investigators took all kinds of extraordinary measures to try to figure out who mailed the anthrax-filled letters that killed five people, scared the country half to death, and have jumped back into public consciousness, thanks to a series of independent reviews over the last six weeks.
But even by the outsized standards of this anthrax case, one step stood out: an attempt to, in effect, reverse-engineer the mailings that carried the killer spores, based on microscopic differences between the blue eagles imprinted on the envelopes.
The envelopes were an immediate locus of the investigation. Forensic technicians from the FBI Laboratory and the U.S. Postal Inspection Service ran all kinds of tests on the envelopes and letters recovered from the anthrax attacks. Most of them went nowhere.
“None of the envelopes exhibited indented writing, watermarks, hair, or latent fingerprints,” notes the Justice Department’s case summary (.pdf). Neither did the tape that sealed the envelopes, or the fibers collect from the lethal deliveries.
There was “a minute quantity of human DNA was detected on the envelope mailed to Senator Leahy,” the summary adds. “But laboratory analysis revealed that this DNA was inadvertently contributed by the FBI Laboratory technician who conducted the initial DNA analysis.”
Just about the only exams that were helpful at all were the thin-layer chromatography and solubility tests performed on the ink samples from the handwritten addresses on the front of the envelopes. Those tests showed that the same pen was likely used to address the envelopes to NBC’s Tom Brokaw and to the New York Post. A separate pen was used in the envelopes sent to Senators Tom Daschle and Pat Leahy. (The letters themselves were photocopies; the originals were never recovered.)
There were still one potential lead left, however. All four envelopes were of the same type — 6 3/4 inches wide, pre-stamped with a blue eagle logo, and made by the MeadWestvaco Corporation between January 2001 and June 2002. But they weren’t exactly alike.
The printing plates that produced those stamps were made of a flexible polymer material. Which means there were microscopic differences between the eagles — the result of tiny irregularities that arose as the printing plates pressed ink onto the envelopes. A little excess ink or a slight abrasion could cause small changes. In theory, those small changes could identify approximately the point within a press run when the killer mailings were produced.
But to make it work, investigators had to take some over-the-top actions. Step one: Collect 290,245 of the so-called Federal Eagle envelopes, to figure out what the original 2001 print run looked like, and how it was distributed. Step two: Print up hundreds of thousands of additional envelopes themselves.
In December, 2006, U.S. Postal Inspection Service agent Tom Dellafera traveled to MeadWestvaco’s Altoona, Pennsylvania, production plant, and ordered a print run of a half-million of the so-called “Federal Eagle” envelopes. By comparing the microscopic differences in these blue eagle stamps to those in the original envelopes, Dellafera’s team was able to point to the part of the press run that produced the envelopes used by the anthrax mailer.
Records showed that this portion of the January 2001 to June 2002 run was sold by 45 offices in Virginia and Maryland — including Frederick, Maryland. That’s where Bruce Ivins, the Army biodefense researcher ultimately blamed for the mailings, lived and worked. It was hardly irrefutable proof of a crime. But it was another indicator.
“It showed you’re in the right bus,” Dellafera says. “After that, the value crashes.”
People looking for the veritable smoking gun or for a CSI-style resolution to the anthrax case are bound to be disappointed. Put all the clues together, and a potent, if circumstantial, case emerges, investigators insist. Ivins’ swiss-cheese alibis, his violent fantasies — add them to the attack spores’ genetic fingerprint and the envelopes, and the whole starts to appear greater than the sum of the individual parts.
“Out of context, it’s all pretty unpersuasive,” says one source, close to the investigation. “Taken all together, it’s convincing.”
Photo: Department of Justice
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