FBI's database of anonymous letters

[Khoder bin Hakkin]

[Reformatted for legibility.  Please take the few moments required to
present documents in a readable manner.  KMSelf]

http://www.fbi.gov/page2/page2.htm

Anonymous Letters

    The Anonymous Letter File (ALF) is an image-oriented database housed
    in the Questioned Documents Unit of the FBI Laboratory. The
    repository houses letters from anonymous sources, categorizing
    entries based on target (recipient of letter), method of
    preparation, and content.

    Established in the 1930s, the original ALF was a unique and useful
    resource for law enforcement.  Originally, index card-sized sections
    of a note's text was from a photograph of the original anonymous
    letter and entered to the database with the written portion of its
    envelope. The entry was filed based on its geographic origin
    (determined by the post mark), nature (hate or demand note) and the
    method of communication (hand-written, typed, etc.). During a
    search, when a Laboratory Technician detected similarities between
    two or more entries, the available content of those notes would be
    further examined (remember, only an index card-sized portion was
    initially used). If an association still appeared likely, an
    Examiner would then conduct a more thorough comparison including an
    examination of handwriting characteristics.

    In the early 1980s, the database was upgraded to include
    video-camera-captured images of letters. The images were stored on
    disk and the text of the entire letter was retyped for comparison.
    The new system also enabled special attention to be given to
    vocabulary, spelling habits, and the topic that a letter addressed.
    Even with this more advanced system, a Questioned Documents Examiner
    still studied the hand writing or printing methods of the associated
    letters looking for a stronger connection.

    The Laboratory's current ALF system, updated in the 1990s, is even
    more advanced. Instead of capturing an image of a letter by video
    camera, images are scanned onto a computer hard drive with back-ups
    made on compact discs.  Comparison is then conducted based on
    target, method of preparation, and content.

    The associations that result from ALF searches can prove invaluable
    in FBI and other law enforcement investigations.  Frequent topics of
    anonymous letters include bomb threats, environmental concerns,
    abortion politics, and gun control.