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Monday, September 24, 2007

The purpose of the Detail is to help keep you informed of the current state of affairs in the latent print community, to provide an avenue to circulate original fingerprint-related articles, and to announce important events as they happen in our field.
Breaking NEWz you can UzE...
compiled by Jon Stimac

FBI Updating Fingerprint Servers TECHNOLOGY NEWS DAILY, AZ - Sept 20, 2007 ...the contract is designed to upgrade the FBI’s existing servers, giving them additional processing power...

Man Indicted in 1971 Beating Death DAYTON DAILY NEWS, OH - Sept 20, 2007 ...crime lab was able to use fingerprints left at the scene to identify the suspect...

Fingerprints Don't Match With Accused  SIFY, INDIA - Sept 19, 2007 ...the court was told that it was difficult to have conclusive opinion on the prints...

McConnell Cleared Over McKie Row PAISLEY DAILY EXPRESS, UK - Sept 19, 2007  ...the former First Minister has been cleared of misleading Parliament in the latest twist in the McKie case...

Recent CLPEX Posting Activity
Last Week's Board topics containing new posts
Moderated by Steve Everist

Articles Wanted
Charles Parker 26 Sat Sep 22, 2007 8:23 pm

Interesting Patterns
Ann Horsman 645 Fri Sep 21, 2007 7:58 pm

Statistics and Misidentifications - The weeks Detail
Michele Triplett 20550 Thu Sep 20, 2007 11:32 am

FP and ID Magazine
Charles Parker 209 Tue Sep 18, 2007 11:57 pm

need help from CA AZ and NM clpex peeps, please
sandra wiese 881 Tue Sep 18, 2007 11:32 pm

LP Distortion and Documenting ACE-V Workshops
Lisa Corson 167 Tue Sep 18, 2007 3:58 pm

September Newsletter
fpsociety 199 Tue Sep 18, 2007 12:18 pm

How much weight does an open field have?
S. Siegel 715 Sun Sep 16, 2007 10:14 am



Updated the Fingerprint Interest Group web page with FIG # 14.

Updated the McKie page with over 50MB of new data including images from the SCRO Presentation at Tulliallan and court transcripts from the testimony of Charles Stewart, Dave Grieve, Fiona McBride, Hugh MacPherson, Pat Wertheim and Shirley Cardwell / McKie.


Last week

we looked at the September IAI update by Joe Polski.

This week

we look at a hypothetical conversation between examiners.  Although it is based on real events and real images, it has been scrubbed to protect sources yada yada.  If they wish to shrug anonymity and participate in further public discussion, or if others wish to continue the discussion, I feel it would be productive and beneficial.  The more we discuss and lead transparent efforts to better our discipline, the stronger it becomes.  The more we are ready to address these concepts on the witness stand, the stronger we become.

Inconclusive Comparison and Dialogue
by Anonymous Examiners

The background is that this is a latent print from a residential burglary, the subject has been named by the detective (as opposed to being an AFIS hit), and there are two other latent prints that were not made by the suspect.  This one is from a probative object in the case.

Examiner 1: I'm not saying it's him and I'm not saying it isn't. Thank goodness this one isn't my case!  All I'm saying is that it's interesting distortion making for an interesting comparison. 

Examiner 1: I'll go ahead and tell you that out of 7 people in my office, not one of them would call this.  There might be someone in the world that might, but I doubt it.  However, the interesting thing is that out of the 7 examiners, 4 said insufficient for identification and therefore ended the analysis and didn't go any further, and 3 said although it wasn't suitable for identification, that it was suitable for comparison and therefore they would proceed to comparison and evaluation.  After doing so, all 3 were inconclusive, stating that although there was insufficient detail for an ID, there was nonetheless sufficient agreement that they couldn't eliminate the subject as being the source of the latent print.  They also felt that 2 problem areas fell on the edge of movement and were not reliable.  The "suitable for ident" versus "suitable for comparison" is a topic that sometimes divides our 7 examiners.  I find it difficult to use "suitable for comparison" on all latent prints, but I do use it on occasion.  For me personally, this comparison is at the bottom of my personal rung for an inconclusive determination due to the limited quality and quantity of detail in the latent print.  Until I re-print the subject, I'm not completely sure whether this is a double-tap (the top and bottom being from the same friction ridge skin) or movement (the top being from a different area of friction ridge skin).

The comparison could be broken into 3 parts: Latent to Latent (top to bottom), Latent Top to Tenprint, and Latent Bottom to Tenprint.

Examiner 2:
I don’t know if it’s my old age or the fact that I’m nearing the end of my 30+ year career without any bad idents (to my knowledge, thank God) and I just want to end it that way.  But, I don’t think I could sleep at night on calling this an ident.  Too much conflict (in my own mind) which is my “red flag” to conclude a “no value” for identification purposes.  On the other hand I would assume that there are some examiners that might call this an ident.  I respect that opinion, but this is one of those “error on the safe side" for me!  Call me Mr. Conservative.

Examiner 3:
I must agree to not calling this an ident.  Too much going on for me.  I would also have to fall back and re-group at another day and time.

Examiner 4: I, on the other hand, am the anti-conservative and love the opportunity to take a chance. However, this is not a print I would be willing to take a chance on. It is evident that there is a problem whether it be from movement, distortion, placement, choose your own term, but I can’t conclusively state that the discrepancies are a result of that phenomenon. I’m with Mr. Conservative in stating that I would let this one go and live to fight another day. J

Examiner 5: Ditto. If you don’t call it, what’s the worst that can happen? The guy walks, but you still have your reputation. If you call it wrong, no matter how honest your opinions or intentions, you have lost considerably more. You can’t unscramble that egg!

Examiner 1:
Generally in this office an Inconclusive is used when the exemplars are incomplete (ie tip latent and the exemplars are not recorded that high). Personally if I have a latent that is a tip, phlange, or from a palm print and I do not have the exemplars necessary for a complete comparison I prefer the term “incomplete analysis”. However the term inconclusive is very seldom used when there is a sufficiency problem with the latent print and not the exemplars. A couple of us will use it for sufficiency issues of a latent print (not suitable for identification but suitable for comparison) but when that happens in this office we have a problem and lines in the sand are drawn and battle formations are made. Tough to get one approved on a Technical Review.

Examiner 6: 
Personally, I like Suitable for Comparison.  Too many times trying to determine Suitable for Identification is difficult when it's on the fence because you don’t have any reference to compare it against.  Being Suitable for Comparison is just as it says…..if there are some ridges there and if I even want to try and refer to any set of knowns, it's Suitable for Comparison.  That doesn’t mean it's identifiable even with a good set of knowns to compare against.  I think the term inconclusive is tremendously underused in our industry.  Why is everyone so afraid of that word?  There isn’t enough information to identify the latent.  But there also isn’t enough information to exclude (there needs to be data to support the exclusion).  That leaves INCONCLUSIVE.  Forensically it's a moot point.  You can’t say either way.  The point is that you did look at it… did compare it, and I think that means something.

Examiner 1:
Well said. I should try to explain why I am having difficulty. In the past 8 years I have used inconclusive more than in the first 22 years. For those 22 years I got quite comfortable with a set limit. Not that I could not go under the limit if the information was present to do so, and in fact I did on several occasions. But now that I have accepted the concept of Suitable for Comparison I have to readjust my limits and I am having a difficult time with where that limit is.  Some in my office who argue against "suitable for comparison" (SFC) and prefer "suitable for identification" (SFI) would say that you could say inconclusive on a single ridge with a single characteristic. Now I can see that as a possibility (whatever that means) but not as a realistic one. I do not think anyone would use the SFC for a single ridge or characteristic. So how far down do I go? Do I need at least some other features present that are in a definable, clear, concise unit relationship? What about patterns? We have all been to that place where we have a whorl pattern and cannot see diddly squat detail in it but yet we know we can eliminate a subject that has all loops or arches. For me there has to be some definable relationship between some arbitrary features that are clear and concise and reliable (if I say that might be an ending ridge----then it is not reliable).  You grew up with SFC (I think). SFC is more difficult for me because I have to readjust my limits. I think it is good but readjusting my limits is killing me sometimes. Inconclusive----you are right it is much underused. I think it goes back to SFC and SFI. Someone who is SFI when they have one that is not identifiable then it is non-suitable, end of story. But with those that have adopted with SFC then an exclusion is on the same level and standards as an identification (they both have equal footing and importance). For SFI a different level of standards exists. With SFC because the ID and Non-ID are on the same level you are going to have more inconclusives due to the borderline or gray area between the two. At least that is my two cents worth. Perhaps the best question yet: Can you tell me at what point or level do you move from Non-Suitable for ACE to Suitable for Comparison?  At what point do you go from “this is not good for anything” to “Yea, I can compare this?”  That is my corundum.

Examiner 6: Well, I would love to tell you something like you need to connect with your “chi” and become one with the latent, but it's much more mundane than that.  I think everyone is familiar when they are looking at a latent and they can see pattern or flow (Level 1) and a few decent, strong characteristics (Level 2) and if you’re lucky, maybe some pores and clear ridge edges with some fluctuation (Level 3).  Now, is it enough to make you pick up a fingerprint card (or would pick up a card if you had one) and look,”just to see if maybe there is something similar that I might want to take a closer look at”?  Then that is Suitable for Comparison……because you just compared it, even if it is just a cursory look.  

Examiner 1: I think my “chi” has connected with my “chong” and hit the comedy tour. Several years ago (about 5) someone told me that if you got to put a glass on it then it is suitable for comparison. That did not work for me because I put a glass on everything.  Then a couple of years ago someone told me very close to what you have stated. It went something like this: “One, do not even think about counting any points, you look and if you see any clear ridge flow and within that if you can see 2 or 3 characteristics then you have one for comparison. Do not worry or consider the amount of detail you have until you have completed your comparison. Then you sit back and consider what you have. If not enough for an ID then dive back in and look for 3LD. If still not enough then perhaps some enhancement. Only when you have exhausted all approaches then you consider what you have. If you start counting features right off the bat and you do not see enough, then you are going to fixate on that decision. Do not count what is up front but only add up what you have in the end.”  That is what I have been doing, but in all honesty it is difficult to get a case through Technical Review when the person doing the Review does not look at it the same way you do. I appreciate what you have said. I kind of baited you there because I was curious as to how you solve the problem. I like it and I am going to adopt it. Now if I can convince four others. That is going to be a hard ground to plow.  

Examiner 4: I’ve been known to write in my report that the exemplars were missing areas of interest on certain fingers or palms preventing a complete examination at this time. I hesitate to use inconclusive in that arena although it definitely applies.

Examiner 1: I dislike the use of inconclusive for describing incomplete or poor exemplars. I did use it for a while in trying to conform to SWGFAST, but it just did not sing, and then I was getting calls from investigators as to what I meant. So now when I have poor exemplars I will say “The analysis is incomplete due to the poor quality of the exemplars  OR  the area needed for comparison was not recorded”. I will only use inconclusive now to indicate a latent print that I cannot individualize or exclude.  I think for poor exemplars a person should describe particularly what is missing or what is needed. Inconclusive just don’t rock my boat for that.

Examiner 2:
Interesting,... I’ll stir the pot. Possible analysis conclusions:
suitable for identification/individualization purposes.
2)      Suitable for comparison (but not necessarily identification / individualization)
3)      Suitable for exclusion only.
4)      Suitable for exclusion / inclusion (base on first level only.)
5)      No value
I suspect there will be some division among the ranks here.  Some are hardliners – no value-of value.  Some like flexibility.  Is this a lack of standards?

Examiner 6:
On your possible analysis conclusions, #1 through #4 can all be covered by Suitable for Comparison.  If there is enough detail in the latent, even if it's just Level 1 Detail, and you would want to compare it to a known it's Suitable for Comparison.  Then you have the standard 3 analysis conclusions:
   Identification (with data to support that)
   Exclusion (with data to support that)
   Inconclusive (with limited data to support either identification or exclusion, or maybe a little of both)

Examiner 2: I’m with you on this.  I just wished to FP community (who ever that my comprise) would all be on the same page (or standard.)

Examiner 1:
SCENARIO - You receive a check with a single ink print on it that was written on the account of a murder victim. The ink print has been recorded, the check processed and no latent prints were developed. You are given two subjects to compare:  Subject A and Subject B. Subject A has all loop patterns and Subject B has all whorl patterns. You then start you examination. Response: It is easy to see that subject A can be excluded as the donor of the ink print in question. However in comparing subject B you cannot individualize his right thumb as the source of the ink print. You tell the investigator you have excluded subject A as the source. What do you tell the investigator about subject B?  1.       The ink print is not suitable for identification with subject B, or 2.       The right thumb of subject B cannot be excluded or included as the source of the ink print on the check. Your analysis is inconclusive.  If you go with 1, how can you say the print can be used for exclusion of subject A but all of a sudden is not suitable for subject B?   Or you could say the ink print is not suitable for identification and not say anything about subject A or subject B. Is that truthful? I would think that subject A’s attorney would like to know that his client could not have left that print at all. Not saying anything at all is not very scientific.  This scenario has been around a long time and I like Suitable for Comparison as it allows me to step out of the box when it is necessary to speak the truth.

Examiner 2: I like many have been struggling with this problem.  I’ll put something on the table (without much thought.)  What if you reported the results something like this?
   Subject “A” is excluded based on general pattern type (level 1.) 
   The question print is a whorl pattern; comprising 35% of fingerprints. 
   Subject “B” possesses patterns within this percentage range.
   No identification can be established with the question print to subject “A” or “B” due to lack of quality/quantity of friction ridge detail. 
It provides the truth about subject “A” and leaves us sitting on the fence with subject “B.”  I know the percentages can vary as well (I’ve read 30 to 35 % etc.)

Examiner 6:
I would report it out something like this:  Subject A could be excluded as the source of the latent fingerprint.  The comparison to Subject B was inconclusive.  Due to limited data in the latent fingerprint, Subject B could not be identified or excluded as a possible source.  I don’t know if it is wise to put probabilities on the likelihood that it is a match.  There are just too many variables.  While it's true that whorls comprise about 30%-35% of fingerprint patterns, but it is misleading if Subject C would have a wide double loop whorl that obviously would exclude him.  A layperson or investigator or attorney may give too much weight to a statement like that when it might not warrant it.

Examiner 4: It seems to me that this is the group to start setting some of these standards and presenting them to the organizations that rule the science. It wouldn’t be easy I know but there has to be some level on which we agree.  I hope someone is writing this stuff down.

Examiner 7 who has been watching from the sidelines: This goes to the heart of "sufficiency" and reporting, and these exchanges are being documented and will be presented to SWGFAST when thes topics arise.  In fact, I write this from SWGFAST this week!  However, neither of these sections are open for edit at this time.

Examiner 4:
And so we continue blindly down the path waiting for someone to do something but never taking the reins ourselves.  It will have to be several States or group entities to get something looked at on a National level. One person or one state won't be enough to get a push. It has to be us. This group needs to be the driving force.

Examiner 1: For my section you have three that will go with Suitable for Comparison and four that go with Suitable for Identification. We have no SOP governing which one is top dog.  So how do you convince, mandate, make someone to accept SFC when they absolutely do not believe in it.  Let the battle begin.  Got to close this off and finish my Power Point for Court. It is nice to have a computer to flip back and forth between a couple of programs. Work on one and flip to the other.  I have to go, so someone drag this over to CLPEX.

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Until next Monday morning, don't work too hard or too little.

Have a GREAT week!