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Monday, July 8, 2002

BREAKING NEWz you can UzE...

BidNow week
This week, instead of listing something of my own, I will refer you to the most unique fingerprint-related ebay auction I have seen in a while.  I (Printman1001) am currently the high bidder for the IAI, so keep that in mind if you planned on bidding.  I believe the auction is over in a few hours anyway.   I was glad to hear that the IAI was interested in purchasing and preserving this wonderful piece of history.  For more on the history of this item visit the "history in full" link within the auction.

Couple Stab Each Other to Death -01 July, 2002 - itechnology.co.za  -  "A husband and wife in Germany apparently stabbed each other to death during an argument, according to police on Monday.  Bodies of the 39-year-old man and his 36-year-old spouse were found in a pool of blood in the family room of their home in Bavaria.  Each body exhibited deep wounds and the murder knives bore the fingerprints of the respective victims.  Police ruled out foul play by a third party, especially after relatives said the couple had a history of dramatic marital strife. - Sapa-DPA"

That is the entire story.  How unusual that blood prints of value were found on BOTH knives...  And both victims (suspects?) were identified!


Good morning via the "Detail," a weekly e-mail newsletter that greets latent print examiners around the globe every Monday morning. 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.

Last week, we looked at the ABFDE Daubert Symposium held in Las Vegas.  This week, we explore the use of Adobe Photoshop for the demonstration of uniqueness. 

I had several responses when I announced I would be doing a Detail on the use of PhotoShop.  Excitement was the main theme, followed by various thoughts on the use of court charts.  Of course, everyone has their own opinions and department policy regarding the use of charts in court, so I won't spend much time on that subject.  The fact is, if there were a major case at your department and the prosecutor insisted on an in-court demonstration, you or someone in your office would be scrambling to scrape something together in PowerPoint or PhotoShop, etc...  Unless you already know one of the programs well, this might be a major undertaking.  Of course, you could always call me up and say, "Hey!... I heard you can chart prints in PhotoShop!"  And I would say, "Yeah, and I charge an arm and a leg!"  I would rather spend my time putting together a training course and teach you how to do it. (which I am currently doing)  But first, you have to recognize the potential of this technique and realize how it can impact a jury.

The use of PhotoShop, a registered trademark program of Adobe Systems, Inc., enables a latent print examiner to demonstrate to someone else exactly what they were looking at in a print, and sometimes even show how they were comparing the detail itself.  Through the use of color and shape (NOT lines and numbers), an examiner can demonstrate uniqueness on all three levels.  The use of PowerPoint allows for demonstration on levels one and two, but difficulty is encountered when trying to demonstrate ridge shape.  In PhotoShop, there are many tools other than the "Line" tool to apply color.  Some of the most frequently used tools include the paintbrush and the fill tool, used in conjunction with a selected area.  I wish I could go into detail on each feature, but we will have to save that for class.  I'll cover the basics here.

The general concept is not that difficult to grasp.  In fact, I like to think of the use of PhotoShop in relation to already-used methods of demonstrating to someone what you see.  If you have a difficult latent comparison (that is a match, by the way), I want you to think to yourself how you would chart it up for a reviewer.  Let's say, for example, that it is a borderline print and you know they are going to have to really study the identification for a while to feel comfortable with it.  You would want to show them what features you were studying, so perhaps you would prepare a photographic enlargement and mark a few of the features in color on the enlargement.  Or maybe you wouldn't mark the photograph itself, rather you would get a sheet of acetate and prepare an overlay with the markings.  This is exactly what PhotoShop offers.  Through the use of "layers," markings can be created and can then be turned "On" and "Off" by showing or hiding that particular layer, similar to flipping the acetate sheet over the photograph and back off again.  Any color application tool can then be used to create an endless number of layers, each of which can be turned on/off in sequence to complete the presentation.

So let's say your identification involved level 1 correspondence, a series of unique creases, and correspondence on levels two and three.  Through the use of the selection and fill tools and the line took, level 1 correspondence could be demonstrated.  Crease correspondence could then be highlighted using a consistent color scheme.  Then, ridge by ridge, the print could be explored by highlighting ridge path on different layers while at the same time demonstrating other ridge shape features used during the identification process.  The result might look something like this: (but understand that you have complete control over the timing of revealing the different layers)


This PhotoShop document was very recently used in a high profile murder trial, and involves the print of the victim found in the residence of the suspect.  More details would be given, except that the case is still in progress.  Although this identification was broadcast on Court TV and portions of it are already on the internet, it is presented here only for the purpose of demonstrating this technique.  When this presentation was shown in court, even the defendant was reported to sit up attentively and stare in amazement at the screen in the courtroom.  Needless to say, the impact on the jury was likely just as significant.

During the presentation, the file itself is opened in Adobe PhotoShop.  PowerPoint is traditionally thought of when discussing any public presentation, but it is important to realize that the data projector is simply a method to display what is on the screen of the laptop.   In this case, PhotoShop is started and the print is loaded on-screen.  PowerPoint never comes in to the picture.  Of course, all the layers are hidden to begin with, and then unveiled as the presenter desires.  All of the traditional testimony as to the identification process still applies, so it is beneficial for the testifying examiner to verbally introduce the types of detail present prior to the on-screen display of the print.  In this example, creases play a major part in the demonstration, so not only was the jury introduced to the three levels of detail, they were also told of "occasional features," which include creases, scars, warts, etc...  Of course, as usual the testimony of the examiner in that case is generally what juries remember.  If your demeanor reflects confidence and it is obvious to the jury that you believe in yourself and the identification in question, then that would have just as much or more weight in the eyes of the jury.  But a nice demonstration sure couldn't hurt!  What this technique enables you to do is show the jury WHY they should be confident about the evidence.

After the examiner presented this on-screen comparison to the court, the following chart was introduced to demonstrate where the print had come from, and also to give the jury something to take back to "the room."  I think the prosecution had the below image printed out in a 4X6 format.  No 4 FEET by six FEET!!  Talk about an impressive color display!

Chart Page

Of course, a generic print could be charted to simply demonstrate the identification process, and that could be presented in this manner in court.  Some agencies chart each identification presented in court, some chart only one, some use a generic set of court charts, and others use no charts.  From talking with supervisors around the country (and the world,) the consensus seems to be that the field seems to be moving toward demonstrating identifications in court.  The trend is moving away from identification "because I said so" to a documented demonstration of the process, and possibly of the evidence in that particular case.  For that reason, these types of charting techniques using PowerPoint or PhotoShop, should be studied by the latent print examiner and practiced so when that case does come up, you aren't left scrambling.  Or calling me.  :)~

I would also like to thank Steve Greene of the Army Crime Lab for his assistance in helping me turn an layered Adobe PhotoShop file into a timed GIF file for display on the internet.  Now that I know this conversion process, look for more such examples in the future!  And if you have a charted print that YOU would like to present, type up a synopsis to go along with it, and submit it for publication in the Detail.  Remember, this is YOUR newsletter!

So... do you have strong feelings on whether or not courtroom demonstrations should be used to show the jury 1) the identification process AND/OR 2) the actual identification in that case?  Or perhaps you would like to contribute to the discussion on how you have demonstrated uniqueness.  Visit the
CLPEX chat board (http://www.clpex.com/phpBB/viewforum.php?f=2) for informal banter about the Weekly Detail.  The onin.com forum (http://onin.com/fp/wwwbd/) is also available for more formal latent print-related discussions.


UPDATES on CLPEX.com this week...

Updated the bookstore to reflect quite a few new sold books and a few new additions.  There has been quite a lot of activity on the only online latent-print bookstore!

T-shirt orders continue to flood in.  I have ordered another hundred shirts!!  Look for them in Vegas.

Feel free to pass the link to The Detail along to other examiners.  This is a free service FOR latent print examiners, BY latent print examiners. There are no copyrights on The Detail, and the website is open for all to visit.

If you have not yet signed up to receive the Weekly Detail in YOUR e-mail inbox, go ahead and join the list now so you don't miss out!

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

Have a GREAT week!


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