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Last Updated

11 Jun 2003

    Source: Linguistic/Behavioral Analysis of Anthrax Letters, Critical Incident Response Group, National Center for the Analysis of Violent Crime. FBI, November 9, 2001.


Letter 1
One page, hand-printed letter
Transmittal envelope, also similarly hand printed
Addressed to "NBC TV Tom Brokaw" No return address
Postmarked Trenton, NJ 09/18/2001 (Tues.)

Letter 2
One page, hand-printed letter
Transmittal envelope, also similarly hand printed
Addressed to "NY Post" No return address
Postmarked Trenton, NJ 09/18/2001 (Tues.)

Letter 3
One page, hand-printed letter
Transmittal envelope, also similarly hand printed
Addressed to "Senator Daschle 509 Hart Senate Office Building"
Return address "4th Grade, Greendale School, Franklin Park, NJ"
Return address zip code "08852"
Postmarked Trenton, NJ 10/09/2001 (Tues.)


It is highly probable, bordering on certainty, that all three letters were authored by the same person. Letters 1 and 2 are identical copies. Letter 3, however, contains a somewhat different message than the other letters. The Anthrax utilized in Letter 3 was much more refined, more potent, and more easily disbursed than letters 1 and 2.

In the past, the public has helped the FBI solve high profile investigations that involved writings by coming forward to identify the author, either by how he wrote or by what he wrote. We are asking for the public's help here again in the same way.

While the text in these letters is limited, there are certain distinctive characteristics in the author's writing style. These same characteristics may be evident in other letters, greeting cards, or envelopes this person has written. We hope someone has received correspondence from this person and will recognize some of these characteristics.

The characteristics include:

1. The author uses dashes ("-") in the writing of the date "09-11-01." Many people use the slash ("/") to separate the day/month/year.

2. In writing the number one, the author chooses to use a formalized, more detailed version. He writes it as "1" instead of the simple vertical line.

3. The author uses the words "can not," when many people prefer to spell it as one word, "cannot."

4. The author writes in all upper case block-style letters. However, the first letter of the first word of each sentence is written in slightly larger upper case lettering. Also, the first letter of all proper nouns (like names) is slightly larger. This is apparently the author's way of indicating a word should be capitalized in upper case lettering. For whatever reason, he may not be comfortable or practiced in writing in lower case lettering.

5. The names and address on each envelope are noticeably tilted on a downward slant from left to right. This may be a characteristic seen on other envelopes he has sent.

6. The envelopes are of the pre-stamped variety, the stamps denoting 34 cents, which are normally available directly from the post office. They are not the traditional business size envelopes, but the smaller size measuring approximately 6 1/4" x 3 ".


Based on the selection of Anthrax as the "weapon" of choice by this individual, the offender:

is likely an adult male.

if employed, is likely to be in a position requiring little contact with the public, or other employees. He may work in a laboratory. He is apparently comfortable working with an extremely hazardous material. He probably has a scientific background to some extent, or at least a strong interest in science.

has likely taken appropriate protective steps to ensure his own safety, which may include the use of an Anthrax vaccination or antibiotics.

has access to a source of Anthrax and possesses knowledge and expertise to refine it.

possesses or has access to some laboratory equipment; i.e., microscope, glassware, centrifuge, etc.

has exhibited an organized, rational thought process in furtherance of his criminal behavior.

has a familiarity, direct or indirect, with the Trenton, NJ, metropolitan area; however, this does not necessarily mean he currently lives in the Trenton, NJ, area.. He is comfortable traveling in and around this locale.

did not select victims randomly. He made an effort to identify the correct address, including zip code, of each victim and used sufficient postage to ensure proper delivery of the letters. The offender deliberately "selected" NBC News, the New York Post, and the office of Senator Tom Daschle as the targeted victims (and possibly AMI in Florida). These targets are probably very important to the offender. They may have been the focus of previous expressions of contempt which may have been communicated to others, or observed by others.

is a non-confrontational person, at least in his public life. He lacks the personal skills necessary to confront others. He chooses to confront his problems "long distance" and not face-to-face. He may hold grudges for a long time, vowing that he will get even with "them" one day. There are probably other, earlier examples of this type of behavior. While these earlier incidents were not actual Anthrax mailings, he may have chosen to anonymously harass other individuals or entities that he perceived as having wronged him. He may also have chosen to utilize the mail on those occasions.

prefers being by himself more often than not. If he is involved in a personal relationship it will likely be of a self serving nature.

Pre-Offense Behavior

Following the events of September 11, 2001, this person may have become mission oriented in his desire to undertake these Anthrax mailings. He may have become more secretive and exhibited an unusual pattern of activity. Additionally, he may have displayed a passive disinterest in the events which otherwise captivated the Nation. He also may have started taking antibiotics unexpectedly.

Post-Offense Behavior

He may have exhibited significant behavioral changes at various critical periods of time throughout the course of the Anthrax mailings and related media coverage. These may include the following;

1. Altered physical appearance.
2. Pronounced anxiety.
3. Atypical media interest.
4. Noticeable mood swings.
5. More withdrawn.
6. Unusual level of preoccupation.
7. Unusual absenteeism.
8. Altered sleeping and/or eating habits.

These post-offense behaviors would have been most noticeable during critical times, including but not limited to: the mailing of the letters (09/18/01 and 10/09/01), the death of first Anthrax victim, media reports of each anthrax incident, and especially the deaths and illnesses of non-targeted victims.

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