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Samir Kantilal Shah (Unregistered Guest)
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Posted From: 239-240-91-219.static.youtele.com
Posted on Monday, June 22, 2009 - 06:45 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

How long the fingerprint impressions remain on the ORNAMENTS ( made up of metal-Copper / gold/ silver) because of sweat / or handling by hands if placed in a cardboard box in a locker and left untouched. After how days or months or years the finger prints are not detectable ?
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Margaret J Leonard (Maggie)
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Username: Maggie

Post Number: 2
Registered: 02-2009
Posted on Wednesday, February 11, 2009 - 03:13 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Thank you for such a detailed and helpful reply. I have seen photocopies of the two items in question, and there are obviously other marks on them though only the three identified ones are highlighted. The report says: "A number of fingerprints had developed on both exhibits but on examination the majority were of a fragmentary nature and disclosed insufficient ridge characteristics for any positive identification." I have no idea what was found on the other 28 documents.

I suppose my original question amounted to this: if a suspect were careless enough to leave fingerprints on correspondence, is it likely that there would be only three on thirty items? I understand from what you say that the answer is "yes" - but I'd love to know who made the other prints. Unfortunately the report only says what is helpful to the side that commissioned it!

Thanks again.




(Message edited by maggie on February 11, 2009)
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Webservant (Member)
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Post Number: 351
Registered: 03-1997
Posted on Monday, February 09, 2009 - 08:15 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Yes, it is reasonable.

The multitude of variables impacting how many identifiable latent prints are developed means that a number from zero to many more than nine may be reasonable.

What is not reflected in your wording is how many other tiny fragmentary impressions were present, but not suitable for identification, on the many documents. It is not unusual for there to be many such fragments, smudges, and other finger marks left by persons handling the documents. It is also not unusual for there to be no mention of such tiny fragments in the forensic report, because they are not "identifiable" and thus thought to be not of evidentiary value (neither exculpatory nor incriminating).

There is ongoing research into procedures and tools that will eventually enable objective scientific comparison of some of those tiny fragments now ignored because they are insufficient for positive identification (not identifiable). Statistical probability studies will eventually enable objective, scientific determination (for example) that a tiny fragmentary impression is consistent with friction ridge detail on a suspect or victim's finger and has been found to occur only X number of times in the relevant population.

The soon-to-be-released report from the National Academies of Science is expected to be critical of the amount of statistical foundation work (much of it recent) supporting the current practice of testifying to "positive identification" (individualization) of latent prints (and similar probability assertions in other forensic sciences).

The NAS report is also expected to identify the need for research to support the scientific application of statistical probability to the comparison of tiny fragmentary impressions (such as those having only perhaps four or five level two details) that are now ignored, but may be of great value for statistical probability association with suspect or victim friction ridge impressions (providing valuable exculpatory or incriminating evidence).

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Margaret J Leonard (Maggie)
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Username: Maggie

Post Number: 1
Registered: 02-2009
Posted on Saturday, February 07, 2009 - 05:34 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Thirty items (envelopes and their contents) were examined for fingerprints. The envelopes had been franked in a postroom, and had then gone through the normal postal service. Most of the envelopes and contents were opened by the same person after delivery, and were handled by several others afterwards. They were then kept for eighteen months in various drawers and folders before being collected and tested for prints. Only nine identifiable prints were found on the thirty items. Three of these belonged to a suspect, two being on the front surface of an envelope, and one on the inside of a card.

My question: is this a reasonable outcome to expect in these circumstances?

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