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Gerald Clough
Posted on Tuesday, March 30, 2004 - 12:27 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Someone can correct me if my information is out of date. FBI files were kept in large groups by age ranges. Beyond a certain age, the person was assumed to be either dea or so old as to be an unlikely criminal. Now that system was intended to make manual searches more efficient. Today, there is a greater dependence on electronic storage, but paper is still very much in use. Storing paper is a problem, as is the large volume of incoming non-criminal cards.

A print can be "changed" surgically, since it is skin, but not into another believable fingerprint. Surgical alteration can obscure the ridges, but that just leaves one with distinctive evidence of the alteration. And, you'd have to do all ten fingers. And you'd be left with identifiable palms. It's been tried.

Fingerprint powders can contain any number of substances. Any stable, very fine powder is a potential component. Componants can be chosen for their color and/or their ability to react to ultraviolent light. They may also contain a ferrous metal, in order to be applied with a magnetic wand. Some early powders contained substances that would not be considered safe today. I suppose the most common powder is black powder based upon volcanic products in place of soot or lampblack in early formulations.

Scrubbing a smooth object with a cloth would likely remove fingerprints. But some surfaces, like paper, can absorb skin secretions and wouldn't be affected much by rubbing.

A person who is in custody would have fingerprints taken by force. A mere suspect could be compelled to submit to printing, depending on the facts. Of course, most persons who become suspect in serious crimes have been arrested in the past and will have had prints recorded.

The traditional management of fingerprint cards was in rooms filled with filing cabinets. Cards can be filed in a particular order by a clever coding that tends to absorb differences in how various classifiers code the prints of one person. The development of a workable filing system was one of the earliest triumphs in fingerprint practice.

The and links to the left will provide much more information.
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Linda Yang
Posted on Monday, March 29, 2004 - 08:01 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

The Identification Division of the FBI maintain files of fingerprints. Are the files overcrowded? If so, what happens if a person dies? Does the fingerprint of that person gets deleted?

Can a finger print be changed surgically?

What is in the powder that is used to expose a fingerprint?

Can a towel remove a fingerprint completely?

What happens if a suspect refuses to have his/her fingers printed?

Before the systems for electronics storage was developed, how were fingerprints stored?

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