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Webmaster
Posted on Sunday, May 21, 2000 - 09:42 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

1. Making transparency enlargements and overlaying even consecutive inked prints would reveal that because the skin is very elastic, you will never have two inked prints or two latent prints, etc., that would exactly overlay... sometimes pretty close, but just as the "one expert" explained, not exactly the same. Push on you fingertip skin and you will see that you can move it around...

2. Because an expert CANNOT know what was left on the finger (popcorn oil, Vitalis, natural secretions, etc.) it is impossible to venture a guess as to how old a latent print could be? The expert had better have ESP if he's going to "date" a latent print by conjecturing that it had to be from natural secretions from the suspect's fingers/palms and could not have been
a contaminated transfer.

--Good luck,
--Ed German
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Ashley Lockwood
Posted on Sunday, May 21, 2000 - 09:38 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

1) I am involved in a case in which the forensics experts differ as to what happens when a print is made:
One "expert" believes that "ridges move" when pressed onto a surface. By this theory, he claims that as the finger presses onto a surface the actual space between ridges can become closer or spread farther apart. This, according to him, can distort a lift, not from movement, but from the actual touching. Thus, no two fingerprints by the same person will be absolutely identical. i.e. a rolled print taken in a police station vs. fingerprint on a knife. Do ridges move??

2) Is there any reliable way to date a fingerprint (and I am not talking about taking one out for dinner and movie)?

Any info would be of help. Thanks in advance!
Ashley Lockwood

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