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Monday, June 11, 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

Carbondale Crime Lab Receives Grant Money  WSIL-TV, IL - Jun 8, 2007 ...the Carbondale forensic crime lab is one of five labs in Illinois benefiting from grant money...

1-hour Prints at the Pawn Shop NEWS LEADER, VA - Jun 7, 2007 ...working steadily, lifting palm and fingerprints from the countertop onto a special, wide tape...

Fingerprint System Helps Nab Taunton Man  BROCKTON ENTERPRISE, MA- Jun 5, 2007 ...police turned to technology to identify a suspected drug dealer who had at least four aliases...

Ministers Face a Grilling in McKie Judicial Inquiry SCOTSMAN, UK - Jun 3, 2007 ...inquiry into the McKie case is set to investigate claims that the cover-up over the affair was linked to fears it would scupper the Lockerbie prosecution...

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

Not so good news out of Florida
Jessica Janisch 4291 Sun Jun 10, 2007 11:35 pm

McKie's facing court appearance?
Daktari 8111 Sun Jun 10, 2007 10:15 pm

Statistics and Misidentifications - The weeks Detail
Michele Triplett 6489 Sun Jun 10, 2007 12:37 pm

Coffey Rules on Reconsideration of Langill Decision
steve ostrowski 1085 Sun Jun 10, 2007 4:34 am

Latent Print Examiner Positions - CONUS/OCONUS
wkpetroka 455 Fri Jun 08, 2007 12:06 pm

This Will Brighten Your Day
Ann Horsman 618 Wed Jun 06, 2007 7:42 pm

Charging the defense for extra photographs and charts?
Cindy Rennie 305 Mon Jun 04, 2007 9:07 pm

CDANIELS 453 Mon Jun 04, 2007 8:07 pm

Digital Photo Logs
Steve Everist 418 Mon Jun 04, 2007 3:15 pm

Ann Horsman 914 Mon Jun 04, 2007 2:07 pm



No major updates on the website this week.


Last week

We monitored an Internet discussion on the importance of known print quality for conclusive results from latent print comparisons.

This week

We begin a series on latent print reporting, process, conclusions, and error.  There are many facets to these issues, so we will proceed in a controlled manner with specific concepts each week.  This will allow time to discuss as well as consider examples for the next week's Detail.  I would like to include as much feedback as possible, so please consider monitoring the message forum for the related thread and posting your comments, or e-mailing me personally.

Latent Print Reporting and Inconclusive Determinations
by Kasey Wertheim

For years, we have heard there are only 2 conclusions in latent print examination. We have heard them in several different forms: either it matches or it doesn't, it's ident or it's exclusion, either the prints were made by the same source or they were not. However, that isn't exactly what many laboratories report. We all report identifications, or the conclusion of individualization that states that the latent print "was made by" the same source as the known print. However, if that conclusion is not reached, the Standard Operating Procedure of many departments then dictates simply reporting that no identification was effected.

The problem is that the phrase "no identification was effected" could mean several different things. It is used by many agencies to report that the print may have been made by that source, but the known prints were illegible. Usually this is followed by a phrase in the report that requests legible or clear known prints.

Another common use of th phrase “no identification was effected” is to report that the print may have been made by that source, but the corresponding area of the known impression was not available to the examiner to compare (ie. when a friction ridge impression that could be either a fingerprint or a palm print is compared against only fingerprints). Usually this result is followed by a phrase in the report that requests additional, complete, or fully-rolled known prints. But the real issue is whether the fingerprint community should also use the phrase "no identification was effected" to report the conclusion that two impressions were not made by the same source, or an “exclusion”.

Some agencies allow their examiners to report exclusions in more clear terms. In these agencies, standard operating procedures encourage the use of more specific wording, such as “L-1 was not made by John Doe”. However, from my conversations with examiners in the field, this is not the norm. It seems that many departments still use the report phrase "no identification was effected" to reflect opinions of exclusion. In order to address the issue of reporting, we must critically examine the hypotheses under which our discipline operates. Our report phraseology is a direct reflection of our hypothesis, worded for a layperson to understand. To lay a foundation for a discussion of latent print hypotheses, we will first touch on the concept of errors in our discipline.

In the field of friction ridge identification, it is commonly felt that the greatest error is to erroneously identify an individual. Fingerprint examinations can result in the loss of life or liberty in the legal system; therefore we set our tolerance for this type of error at the very lowest level possible. I cannot remember a single conversation with a latent print examiner who feels that the severity of an erroneous identification is less than that of a missed identification. The most grievous error is generally considered to be greater when someone is erroneously identified. In statistics, a false positive determination is referred to as a type 1 error. To effect a type 1 error, a scientist incorrectly claims that a result is statistically significant when it really is not. In many disciplines, such as fingerprints, the actions that result from a type 1 error can directly impact life or liberty.

The lesser error is generally considered to be a missed identification, or not 'seeing' or 'calling' a print that actually does match. It is commonly felt that it would be better to err on the side of caution and 'let one go' or 'not call' a print than to erroneously identify an individual. In statistics, an error of omission is referred to as a "Type II error". In science, a type 2 error is a missed opportunity to obtain a result that actually existed. Since scientists think conservatively, a type 2 error is considered much less severe than a type 1 error. In fingerprints, the result of a type 2 error may not directly impact liberty, as would sending an innocent person to jail with a type 1 error. However, there are obvious and sometimes even more serious ramifications to a type 2 error in fingerprints, such as additional actions that are allowed to occur in serial crimes against persons or terrorism related cases.

Most examiners understand the distinction between an erroneous identification and a missed identification, but administrators might not. If an agency has no clear guidelines in place to deal separately with these very different situations in latent print examination, then examiners are left wondering what would happen if an identification is missed. In some cases, agencies initiate punitive action for either type of error as if they were the same. For example, an examiner may be treated as if they made an erroneous identification for not “calling” a difficult match on a proficiency test. Administration may view an “error” as the same regardless of whether it was type 1 or type 2. (example of a miss on a proficiency test) However, there are actually two different types of “missed” identifications that in my opinion, have not been sufficiently defined and distinguished in the past.

In casework situations where an examiner feels pressure to make a determination on limited information, this distinction becomes obvious. In many cases, prints that appear “close” to an examiner, but lack a sufficient detail for individualization are correctly reported as inconclusive ("no identification was effected"). However, I have spoken with examiners who, when faced with this dilemma, simply threw the latent print they lifted and were comparing in the garbage can. Rather than deal with a comparison that was “on the edge,” they destroyed evidence. The problem is realized when it is viewed under the parameters of a new latent print examiner… by destroying a “close” latent print, the new examiner is basically saying that their superiors could not identify that impression. They may be right, but is that a decision you want a new examiner to make? The same argument would apply to a senior examiner who has not had detailed training on the analysis, comparison and evaluation of level 3 detail that a junior examiner has had. How can they make a decision to eliminate the latent print from ever being re-evaluated if they can’t recognize this type of uniqueness? After all, if they could recognize the impression as unique and suitable, they would be able to identify it. If a latent print appears “close” but an examiner “just can’t quite make it”, to throw that latent print in the trash is basically to say “nobody else could have identified it.”

There could be many reasons why an examiner might justify destroying evidence. One might be the fear of missing an identification resulting in peers labeling the examiner as inferior. A certain pride accompanies the recognition of examiner expertise. Another fear might be the loss of self-confidence that accompanies such a situation. However, I believe the most likely root cause of destroying a borderline impression is the fear of not being able to identify a print that someone else can match. In short, it is in an attempt to avoid a situation that could lead to what they perceived might have been an error, but was just a limitation of their own ability. Most examiners are quite comfortable with their definition of sufficiency, but they are very conservative when it comes to situations that involve any type of error.

However, for complex latent print examinations requiring critical discrimination ability, I feel we have not, as a discipline, necessarily defined what action is acceptable and what is not. In fact, I don't think the difference between types of error have even been fully resolved! I think this lack of a clear distinction is based in part on the appearance that our discipline appears to be defining our methodology under one set of hypotheses, when in reality we make examination decisions by operating under two distinctly different sets of hypotheses.

Next week, we will explore the process leading up to the examination, and some of the associated decisions and hypothesis sets for conclusions along the way. From there, we will look at hypothesis sets for the comparison of two impressions followed by some additional discussion about reporting.  At the end of this series, I will combine all of the Details for a comprehensive article, and post it on the website.  But for now, some preliminary discussion on this topic on the message board would probably be productive and lay the foundation Details in the coming weeks.  Here are some controversial views to consider for discussion:

“No Identification was Effected” is not a conclusive determination. Report an exclusion with wording such as “the latent print XX was not made by XX”. If a comparison isn’t quite “enough” for you, but you think it probably matches (and wouldn’t ever fault anyone else for making the match), keep the print in the case (don’t throw it out), and seek another examiner or outside verification. Word your worksheet or report something like “no conclusive determination could be made to the XX finger of XX”. And simply don’t request additional prints. What could be more true than the truth! And if you are ever questioned about why you weren’t sure, if you remain honest with yourself, and what you will probably realize is that you could use some additional training.  Hey… if your agency wants more conclusive reports, perhaps you should seek and they should provide you the opportunity to have more conclusive training!

Here are some critical thinking questions that feed into the preceding scenario:

Do you use the phrase “no identification was effected” to report BOTH inconclusive results as well as exclusions? If not, how do you report an exclusion? How do you report an inconclusive result for a latent print that should be retained as evidence in the case? Does your agency reporting procedure prevent you from reporting an inconclusive? Or an exclusion?

If you saw similarity but not enough for you to personally make a match, would you destroy the print? If you retained it, how would you report your result?

If you kept it and someone else identified it, would you be disciplined in any way? Would you feel inadequate? Doesn’t your agency’s training play into your lack of conclusion?

Use the Board!  And enjoy the concept - this is at the heart and soul of what we do.

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

Have a GREAT week!