It is possible to see enough class charictaristics in a latent that is not of value for identification, but I could exclude. ie latent is a whorl and knowns are all arches yet latent is of poor quality and quantity.
If I am following ACE-V, how do I reach this conclusion? During Analysis I am suppose to look at the latent and decide whether there is enough to individualize. If I come to the conclusion that there is not enough detail there, then I do not go on to the comparison phase. And for good reason I believe, I could see something in the known that might influence my analysis of the latent. So following ACE-V, how could I exclude on a NV print?
Elimination from NV prints
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Andrew Schriever
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In my opinion 'Analysis' is more than just looking at the print to determine if the print is sufficient for individualization. As Ashbaugh puts it, in his 2QA book, "An analysis can be compared to intelligence gathering, a process where one learns as much about the latent print as possible". This 'intelligence gathering' includes an initial determination of value/no value, but is not limited to that. Analysis includes gathering information about substrate, matrix, distortion, presence of Level I-III characteristics, etc. These factors all lend a hand in determining value/no value, but can answer other questions as well (ie. could this print be forged?).
So, just because a print is determined no value for individualization, doesn't necessarily mean that the print has no value for any forensic examination. An elimination based on Level I characteristics is a matter of personal comfort level.
So theoretically for example:
A- Print is not sufficient for individualization but posesses Level I characteristics of a whorl type pattern.
C- During comparison no whorl type pattern was observed on the known impressions.
E- The areas of friction ridge skin represented in the the known impressions could not have donated the unknown impression.
So, just because a print is determined no value for individualization, doesn't necessarily mean that the print has no value for any forensic examination. An elimination based on Level I characteristics is a matter of personal comfort level.
So theoretically for example:
A- Print is not sufficient for individualization but posesses Level I characteristics of a whorl type pattern.
C- During comparison no whorl type pattern was observed on the known impressions.
E- The areas of friction ridge skin represented in the the known impressions could not have donated the unknown impression.
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Danny L. Harness
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Elimination from NV prints
[quote]but I could exclude. ie latent is a whorl and knowns are all arches yet latent is of poor quality and quantity.
The fact that you can eliminate a suspect based only on class characteristics should be grounds to publish in a report. The fact that technically you did not do a comparison, should not conflict with ACE-V protocols.
The fact that you can eliminate a suspect based only on class characteristics should be grounds to publish in a report. The fact that technically you did not do a comparison, should not conflict with ACE-V protocols.
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David Fairhurst
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The thing that interests me in this recurring type of discussion is that everyone seems to view insufficiency as qualitative only.
What about the quantitative aspect?
What if you have a high clarity print that is just too small to individualise?
What if you can see just a small area around the core of a loop?
What if this core has a single rod in the middle and you can see only 3 ridges surrounding it, no endings or bifurcations? (we call these plain staples here in UK)
Could you ever individualise this latent? I think not.
What of you look at your exemplars and there are no cores with single rods and 3 plain staples around it?
Can you exclude that suspect? Of course you can.
The optimum (and scientific) situation would be to say "no insufficiency without comparison". In other words, until I have attempted a comparison I cannot truly say whether a print has value.
Also, results of comparisons should be just that and not result in the classification of a latent as having no value. The only exception to this is the inconclusive comparison. Once you're inconclusive about one suspect you cannot legitimately go on to conclusively individualise another.
But lets bring this back to the real world. We cannot go on comparing every scrappy little bit of detail with endless lists of suspects, always excluding or being inclonclusive, never individualising. We would grind to a halt. We have to make a call, but I don't view it as a scientific evaluation. It's an evaluation of the cost and potential value of our work to the investigation. There comes a point when we have to say that our time and resources can be better spent. The latent is not valueless scientifically but it is a waste of time doing anything with it.
What about the quantitative aspect?
What if you have a high clarity print that is just too small to individualise?
What if you can see just a small area around the core of a loop?
What if this core has a single rod in the middle and you can see only 3 ridges surrounding it, no endings or bifurcations? (we call these plain staples here in UK)
Could you ever individualise this latent? I think not.
What of you look at your exemplars and there are no cores with single rods and 3 plain staples around it?
Can you exclude that suspect? Of course you can.
The optimum (and scientific) situation would be to say "no insufficiency without comparison". In other words, until I have attempted a comparison I cannot truly say whether a print has value.
Also, results of comparisons should be just that and not result in the classification of a latent as having no value. The only exception to this is the inconclusive comparison. Once you're inconclusive about one suspect you cannot legitimately go on to conclusively individualise another.
But lets bring this back to the real world. We cannot go on comparing every scrappy little bit of detail with endless lists of suspects, always excluding or being inclonclusive, never individualising. We would grind to a halt. We have to make a call, but I don't view it as a scientific evaluation. It's an evaluation of the cost and potential value of our work to the investigation. There comes a point when we have to say that our time and resources can be better spent. The latent is not valueless scientifically but it is a waste of time doing anything with it.
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Ernie Hamm
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David,
You are making a very good point about examiners being concerned on decisions with every little scrap of latent print. I read many of these posts and keep wondering where they find all the time for resolving every little issue. There is a job to be done and it is probably becoming more difficult as the technology and the challenges advance.
Under certain circumstances, some opinions can never be fully supported. The key to some decisions can rest in ‘official’ report wording. The manner in which an examiner states their conclusions can handle most future scenarios. Stating that a latent print, any latent print/mark regardless of sufficiency, ‘was not made’ (total exclusion) can be dangerous. We have all heard that an examiner claiming they have NEVER missed an identification is not living in the real world and this is making reference to claimed latent prints with sufficient detail for identification. The marginal inconclusive(?) ones are even more dangerous. “Eromoore” started the thread about excluding a no-value print on class, whorl vs. other. It is interesting that when I was acquiring material on a paper concerning differences in level one appearance, I received illustrations involving, guess what, whorls. The differences were resolved with Galton details and identifications made. However, without that additional detail, the prints may have resulted in an exclusionary (erroneous) statement if the examiner’s policy or personal considerations required some sort of finding. A statement I use in another area of comparative examination is, “An erroneous identification is a miscarriage of justice, but an erroneous elimination is a miscarriage to justice”.
When I was doing case work (Oh, so many years ago!!), I was comfortable in only reporting latent prints of value (value level is another issue also part of this forum) and without mentioning a specific number of prints when it was greater than one. Comparison results would be ‘identified’ or ‘not identified’ and those rare conditional ‘inconclusive’. While it may be a fine point on semantics, “not identified to” does not necessarily equate to “was not made by”. There is some wiggle room when some condition may later change in an examination. IF (and this is a big IF) there are subsequent special requests involving all latent prints/marks/smears/whatever, these can be handled on an individual case-by-case, latent-by-latent basis without significantly interfering with normal case workflow.
Ernie Hamm
You are making a very good point about examiners being concerned on decisions with every little scrap of latent print. I read many of these posts and keep wondering where they find all the time for resolving every little issue. There is a job to be done and it is probably becoming more difficult as the technology and the challenges advance.
Under certain circumstances, some opinions can never be fully supported. The key to some decisions can rest in ‘official’ report wording. The manner in which an examiner states their conclusions can handle most future scenarios. Stating that a latent print, any latent print/mark regardless of sufficiency, ‘was not made’ (total exclusion) can be dangerous. We have all heard that an examiner claiming they have NEVER missed an identification is not living in the real world and this is making reference to claimed latent prints with sufficient detail for identification. The marginal inconclusive(?) ones are even more dangerous. “Eromoore” started the thread about excluding a no-value print on class, whorl vs. other. It is interesting that when I was acquiring material on a paper concerning differences in level one appearance, I received illustrations involving, guess what, whorls. The differences were resolved with Galton details and identifications made. However, without that additional detail, the prints may have resulted in an exclusionary (erroneous) statement if the examiner’s policy or personal considerations required some sort of finding. A statement I use in another area of comparative examination is, “An erroneous identification is a miscarriage of justice, but an erroneous elimination is a miscarriage to justice”.
When I was doing case work (Oh, so many years ago!!), I was comfortable in only reporting latent prints of value (value level is another issue also part of this forum) and without mentioning a specific number of prints when it was greater than one. Comparison results would be ‘identified’ or ‘not identified’ and those rare conditional ‘inconclusive’. While it may be a fine point on semantics, “not identified to” does not necessarily equate to “was not made by”. There is some wiggle room when some condition may later change in an examination. IF (and this is a big IF) there are subsequent special requests involving all latent prints/marks/smears/whatever, these can be handled on an individual case-by-case, latent-by-latent basis without significantly interfering with normal case workflow.
Ernie Hamm
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Wayne Reutzel
- Posts: 19
- Joined: Mon Jan 09, 2006 1:59 pm
As an old timer (like Ernie) I tend to follow his practice and avoid the "general pattern type" comparisons for inclusion / exclusion or inconclusive. Case backlog is only one aspect affecting my decision to avoid this type of comparison; there are others (for a later discussion.) My concern is that we may be forced to "wrestle" in court with this issue whether we want to or not if the defense has an independent expert who arrived at a conclusion of 'exclusion." I can't help but believe that the prosecution would request your presence in court for rebuttal, forcing you to enter an arena that you prefer to stay out of.
I would like to see the fingerprint community come to a firm decision on this matter that all examiners would follow.
I would like to see the fingerprint community come to a firm decision on this matter that all examiners would follow.
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eromoore
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I was generalizing in my opening post. Specifically I have a latent print off of a drug bag that was found in the trash can at a business. This latent is a whorl with a ridge count of 4-5, the known fingerprints of my suspect has only whorls with ridge counts of 12 and up. The few second level details I can see are also not in agreement with any of the known prints. I am comfortable that this is not the suspects latent. So should I not report this as an exclusion? If I am comfortable with it not being his print, how could I not report it in good concious?
I hardly think the person accused to dumping these drugs thinks that it is a waste of time excluding him as the donor.
I do not worry about every scrap of a latent. This latent had potential being "of value" so I photographed it. I decided it was NV and then realized the patterns and details were not the same as the suspects. This is also not a print that could have been left by the normal "passerby" - ie a lift from a door at a business of a burglary - this was found on a drug bag, in a trash can. I think this could be just as important to an investigator in this case to know there is a print that is not the suspects as if I would have identified the print.
I hardly think the person accused to dumping these drugs thinks that it is a waste of time excluding him as the donor.
I do not worry about every scrap of a latent. This latent had potential being "of value" so I photographed it. I decided it was NV and then realized the patterns and details were not the same as the suspects. This is also not a print that could have been left by the normal "passerby" - ie a lift from a door at a business of a burglary - this was found on a drug bag, in a trash can. I think this could be just as important to an investigator in this case to know there is a print that is not the suspects as if I would have identified the print.
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eromoore
- Posts: 4
- Joined: Wed May 03, 2006 12:06 pm
I was generalizing in my opening post. Specifically I have a latent print off of a drug bag that was found in the trash can at a business. This latent is a whorl with a ridge count of 4-5, the known fingerprints of my suspect has only whorls with ridge counts of 12 and up. The few second level details I can see are also not in agreement with any of the known prints. I am comfortable that this is not the suspects latent. So should I not report this as an exclusion? If I am comfortable with it not being his print, how could I not report it in good concious?
I hardly think the person accused to dumping these drugs thinks that it is a waste of time excluding him as the donor.
I do not worry about every scrap of a latent. This latent had potential being "of value" so I photographed it. I decided it was NV and then realized the patterns and details were not the same as the suspects. This is also not a print that could have been left by the normal "passerby" - ie a lift from a door at a business of a burglary - this was found on a drug bag, in a trash can. I think this could be just as important to an investigator in this case to know there is a print that is not the suspects as if I would have identified the print.
I hardly think the person accused to dumping these drugs thinks that it is a waste of time excluding him as the donor.
I do not worry about every scrap of a latent. This latent had potential being "of value" so I photographed it. I decided it was NV and then realized the patterns and details were not the same as the suspects. This is also not a print that could have been left by the normal "passerby" - ie a lift from a door at a business of a burglary - this was found on a drug bag, in a trash can. I think this could be just as important to an investigator in this case to know there is a print that is not the suspects as if I would have identified the print.
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eromoore
- Posts: 4
- Joined: Wed May 03, 2006 12:06 pm
I was generalizing in my opening post. Specifically I have a latent print off of a drug bag that was found in the trash can at a business. This latent is a whorl with a ridge count of 4-5, the known fingerprints of my suspect has only whorls with ridge counts of 12 and up. The few second level details I can see are also not in agreement with any of the known prints. I am comfortable that this is not the suspects latent. So should I not report this as an exclusion? If I am comfortable with it not being his print, how could I not report it in good concious?
I hardly think the person accused to dumping these drugs thinks that it is a waste of time excluding him as the donor.
I do not worry about every scrap of a latent. This latent had potential being "of value" so I photographed it. I decided it was NV and then realized the patterns and details were not the same as the suspects. This is also not a print that could have been left by the normal "passerby" - ie a lift from a door at a business of a burglary - this was found on a drug bag, in a trash can. I think this could be just as important to an investigator in this case to know there is a print that is not the suspects as if I would have identified the print.
I hardly think the person accused to dumping these drugs thinks that it is a waste of time excluding him as the donor.
I do not worry about every scrap of a latent. This latent had potential being "of value" so I photographed it. I decided it was NV and then realized the patterns and details were not the same as the suspects. This is also not a print that could have been left by the normal "passerby" - ie a lift from a door at a business of a burglary - this was found on a drug bag, in a trash can. I think this could be just as important to an investigator in this case to know there is a print that is not the suspects as if I would have identified the print.
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Ernie Hamm
- Posts: 214
- Joined: Sun Jan 22, 2006 10:24 am
- Location: Fleming Island, Florida
- Contact:
Wayne,
Unfortunately, regardless what the fingerprint community would decide, independent examiners are not bound by policies and procedures that exist for organizations and agencies. I would hope a prosecuting attorney would be aware of any independents arriving on the scene, subpoena the individual (with you in attendance?) and learn of any ‘concerns’. Once additional information is known, you should be able to enter any arena and ‘let the games begin’.
Talking about letting the games begin, Eromoore’s additional information and thoughts on the situation opens up several different areas of discussion. However, if the latent is deemed to be of no value, it is of no value and that is the end of it. If you feel other information should be given to an investigator, do so ‘off the record’. I do not see that the presence of a fingerprint, of full value or limited value, made by another person is significant in your example unless you have information that clearly supports how and when the print was placed on the object and if this is material to the issue. You did not find the suspect’s print; does this mean the suspect did not touch the drug bag? You know the answer to that one.
All that being said about this scenario, back to the original premise of whether an elimination on a print of NV should be made? I believe this decision is possible under certain circumstances on a marginal latent OF SIGNIFICANCE that has sufficient detail on any level, just not this example. OF SIGNIFICANCE is important and circumstances are very important. Definition of this is difficult, but one that an examiner should recognize when it presents itself (I’ll know it when I see it).
Unfortunately, regardless what the fingerprint community would decide, independent examiners are not bound by policies and procedures that exist for organizations and agencies. I would hope a prosecuting attorney would be aware of any independents arriving on the scene, subpoena the individual (with you in attendance?) and learn of any ‘concerns’. Once additional information is known, you should be able to enter any arena and ‘let the games begin’.
Talking about letting the games begin, Eromoore’s additional information and thoughts on the situation opens up several different areas of discussion. However, if the latent is deemed to be of no value, it is of no value and that is the end of it. If you feel other information should be given to an investigator, do so ‘off the record’. I do not see that the presence of a fingerprint, of full value or limited value, made by another person is significant in your example unless you have information that clearly supports how and when the print was placed on the object and if this is material to the issue. You did not find the suspect’s print; does this mean the suspect did not touch the drug bag? You know the answer to that one.
All that being said about this scenario, back to the original premise of whether an elimination on a print of NV should be made? I believe this decision is possible under certain circumstances on a marginal latent OF SIGNIFICANCE that has sufficient detail on any level, just not this example. OF SIGNIFICANCE is important and circumstances are very important. Definition of this is difficult, but one that an examiner should recognize when it presents itself (I’ll know it when I see it).