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Monday, May 14, 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

Doctor Removed Suspects‘ Fingerprints  HINESBURG JOURNAL, CANADA May 12, 2007 ...a Mexican doctor surgically removed drug traffickers‘ fingerprints, substituting skin from the soles of their feet...

Fingerprints Solve Catholic Church Fire  INDIANAPOLIS STAR, IN - May 11, 2007 ...fingerprints on a bottle of church wine discarded in a trash bin helped lead investigators to a man...

More Police Discrepancies Revealed MUMBAI NEWSLINE, INDIA - May 11, 2007 ...police admitted in court that they have not recovered the glass on which the accused fingerprints were found...

Man Charged with Home Invasion JOURNAL NEWS, NY - May 10, 2007 ...the print matched by the Sheriff's Department detectives provided the police with enough evidence to charge...

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

 Poll ] Pay Parity
sorbitol Sun May 13, 2007 7:09 pm

Debating research, especially when you do not agree with it!
Dr. Dror Sun May 13, 2007 6:48 pm

McKie's facing court appearance?
Daktari Sun May 13, 2007 4:26 pm

Not so good news out of Florida
Jessica Janisch Sat May 12, 2007 3:56 pm - book launch and site re-structure
Iain McKie Fri May 11, 2007 10:48 pm

Having Trouble Getting Justice?
Dennis Degler Fri May 11, 2007 10:34 pm

Training feedback
Steve Skowron Fri May 11, 2007 5:50 am

Are there any latent examiner's lab that don't verify?
J Fennell Fri May 11, 2007 12:33 am

Fingerprint authenticates Jackson Pollock masterpiece?
Red.Sox.Fan Thu May 10, 2007 8:53 pm

Point Of View: Point Counters and Pseudoscience
Charles Parker Tue May 08, 2007 3:27 pm



I'm safely back home after 8 weeks of travel. Thanks to the many friends and colleagues who kept me in their thoughts and prayers.

Updated the Detail Archives with the website updates for the last 8 weeks of the Detial via e-mail. The Newz will be updated soon for those weeks.

Updated the Smiley Files with four new Smileys from Michele Triplett, Sherrie Hill, Kathleen Bright-Birnbaum, and Brian Segrest! Thanks as always to Bill Wolz for his efforts as our Smiley Czar. Visit the Smiley Files to see these latest additions.


Last week

we reviewed some fingerprint related news and events..

This week

Pat Wertheim brings us a comprehensive guide to reviewing, practicing, and strategizing for the IAI CLPE test.

Preparing for the IAI Latent Print Certification Test

There has been discussion on the CLPEX Chat Board since its inception by latent print examiners preparing for the IAI Latent Print Certification Test. The concern seems to be how to prepare for the test. In this article, I will try to give you some tips on preparation for the test. Years ago when I was teaching an advanced class in fingerprint comparison, I had the opportunity to work with each student individually and get to know them, their habits, their strengths, and their weaknesses. That made it easy to customize a strategy for taking the test for each individual. A “one size fits all” strategy may not work as well, but at the end of this article I will give some suggestions for you personally to customize a strategy based on your own self evaluation.

First of all, check the IAI website for details of the latent print certification program at ( for all of the latest information.

The test is given in four parts. The first three parts are sent in the mail and are proctored. The fourth part is testimony and it will be discussed near the end of this article.

To begin the process, mail a completed application form with all required attachments to the Latent Print Certification Board Secretary. The application goes through the approval process, which may take several months while the Certification Board and your IAI Division committee verify all of your information. Once the application is approved, the first three parts of the test are mailed to a member or your IAI Division Certification Committee. That committee member will contact you to set up a date to take the test.

The three parts of the test you will take at that time are
A. Comparison of 15 latent prints with inked prints. You must correctly identify 12 of the latent prints with no erroneous identifications (80%).
B. Pattern interpretation of 35 inked fingerprints (passing score: 90%)
C. True/False, multiple choice (hereinafter referred to as TFMC) questions over the history of fingerprints, pattern interpretation, and latent fingerprint. (Passing score: 85%)

For most people, section “B.” (pattern interpretation) is not difficult. All of the prints were, to my eye, basic whorls, loops, and arches without any attempt to fool you with trick patterns. None of the prints were smudged or incomplete. Passing this part of the test is, in a word, easy.

Section “C.” (TFMC) is likewise not difficult for the majority of people I have known who take the test. All questions are “true or false” or multiple choice. All of the answers come directly from the resource material, but most are “common knowledge” in our profession if you have been to classes, studied the texts and articles, do both processing and comparisons, and engage in business related discussions with other examiners at conferences. Passing this part of the test is, in two words, pretty easy.

Henry Templeman of San Jose Police Department has done a very good job of writing a “practice test” for people preparing for this part of the test and Ed German has posted Henry’s practice test at his site. For a good idea what the real test will be like, take the practice test at ( ) or access the practice test by going to, click on fingerprints, then click on “expert topics,” then scroll down until you come to the link to Henry’s sample questions.

Section “A.” is the part where most people who “fail” the test have trouble. I dislike the word “fail” in this context because most people I have known personally who did not pass the test had the talent and ability to do so, but were unable to make the required 12 or more identifications in the time period allowed. In a sense, they did not “fail,” they merely did not make enough correct identifications in the allotted time. In other words, they did not “fail” in the classic sense of marking wrong answers. Rather, the answers they got were all correct but they ran out of time before getting enough of the answers correct. This is where the “strategy” I talked about in the first paragraph of this article comes in. When I was still teaching and working personally with my students to prepare them for the test, for many years the pass rate among my students was 100%. Eventually, a few did not pass the test for various reasons, but even by the time I retired from teaching, my students were still running a 90% pass rate or greater.

Why do I think you need a “strategy?” A number of factors apply in answering this question. Some people are “natural test takers” and some people almost literally freeze up at the thought of taking a test. Most of us fall somewhere between those two extremes. The “natural test takers” have developed a subconscious ability to develop and follow a good strategy in taking just about any test and those people have no serious problems with the certification test. On the other hand, those who freeze up at the thought of taking a test need to develop a rigid strategy specifically for the test and they need to practice, practice, practice, in order to cope with their apprehensions and avoid “freezing up” during the real test. Those in the middle will usually do well by learning and, after only one or two practice tests, applying their “strategy.”

So I believe the key to passing the test for many people is simply approaching it with a good strategy.


First, decide in what order to take the three parts of the test. If you believe you are weak at comparisons, my advice is to take the comparison part first, make your twelve identifications, then immediately stop the comparisons and move on to the other parts of the test, the pattern interpretation and the true/false/multiple choice parts. The reason for this strategy is that if you run out of time and have not finished the entire test, you only have to repeat the parts you “failed.” Of course, if you make an erroneous identification, you must retake the entire test. But let’s assume you do not make an erroneous identification and you do get your 12 correct identifications, but you run out of time on one of the other parts of the test. In that case, you do NOT have to repeat the comparisons when you take the test again six months later. You only have to take the part or parts you did not complete. So, if you are slow or weak at comparisons, take the comparisons first, make 12 identifications, and quit that part of the test to move on to the other parts.

On the other hand, if you are reasonably quick with comparisons and believe you can find twelve in six or seven hours or less, my advice is to take the pattern interpretation and TFMC parts first. Get them out of the way and clear the desk for the comparison portion of the test. Then, do NOT quit after 12 identifications, but go for all you can get. It would be easy to quit after 12, but to my mind, if you are better than that, why be a quitter? Some people have said to me, “But what if I get my 12 and go for one or two more, but I try to guess and make an erroneous identification?” My response is, “Why would you ever guess at an identification?” I am not suggesting you “guess,” but go on beyond the 12 identifications to see if you can identify the rest. Don’t be a quitter! Be a cut above and make all the identifications you can!

Now, when taking the comparison portion of the test, here is some more strategy. Separate the latent fingerprints from the latent palm prints. Put the fingers in one stack and the palms in a separate stack. Next, put the fingerprints in order with the easiest ones on the top of the stack and the hardest ones on the bottom; likewise with the latent palm prints. Go a step further and separate the latent right palms from the latent left palms.

Now, separate the known (inked) fingerprints from the known (inked) palm prints. It is my observation that this is one of the hardest “speed bumps” for many people to get over. It has to do with the way your brain organizes material. We are taught to organize fingerprints by suspects’ names. When you are working at your desk, you probably keep the fingers and palms together by suspect name, and that is fine. But in taking the certification test, that habit is counterproductive. It works against you. Break it. If you keep the inked fingerprints and inked palm prints together by name, you waste valuable time flipping through all the palm cards every time you compare a latent fingerprint, and flipping through inked fingerprints every time you are searching a latent palm print.

In fact, let’s take it a step further. Separate your inked prints into THREE stacks – inked fingerprints, inked right palm prints, and inked left palm prints. Now you can compare fingers to fingers, right palms to right palms, and left palms to left palms without having to waste any time flipping through cards you do not need to compare.

Okay, I know you are thinking, “But what if the latent is a little piece of ridge detail and I can’t tell whether it is a finger or a right palm or a left palm?” The truth is that most of the latent prints on the test are not indeterminable little specks of ridge detail, and the one or two that might be will be at the bottom of one of the stacks of latents anyway, so don’t worry about them at this point. We will get to that later in the “strategy.”

So, we are going to begin by comparing latent fingers to inked fingers, latent right palms to inked right palms, and latent left palms to inked left palms.

In taking the comparison part of the test, is important to use “Analysis,” “Comparison,” and “Evaluation” separately. In “Analysis,” you study the latent print thoroughly. The more time you spend on analysis, the less time you will spend on comparison. If you skip a thorough analysis of the latent and go straight to comparison by putting the latent print next to the inked prints, you will lose valuable time. The way to save that valuable time is use a little of it first for a thorough analysis of the latent.

First, pick your best “target group” in the latent print. A “Target Group” is usually a cluster of three or four “Points” that you can memorize and then recognize again. The “best” target group is not always the most bizarre group or cluster of points, but is a group or cluster of points that you can “anchor” to some other feature in the latent print, like the delta or the core. A single ridge ending that you can precisely measure as three ridges directly above the core is a far better target than some strange configuration of points 15 or 20 ridges away, up kind of near the top somewhere. Chose your “target group” based on how exactly you can tie it to the delta or the core. If there is no clear delta or core, use the “type lines” and find a target group on them. (If you do not understand the concept of “type lines,” it is time to pull out the FBI’s booklet, “Science of Fingerprints,” and study your definitions.) A target group right on the type lines, or a ridge or two above or below the type lines, is much easier to find when you are searching the inked prints that a target group somewhere out in left field.

The whole idea here is to pick your target group based NOT on what is the most unusual thing in the latent print, but rather, what will be the easiest and fastest to find in the inked prints. So, during “analysis,” pick your target carefully – then MEMORIZE it. The best way for most people to memorize a target is to DRAW it. Drawing a target programs it into your brain in the same way plotting the points of a latent print into AFIS programs the computer to find those same points in the inked prints in AFIS. For the test, DRAW your target group of points to force your brain to memorize it better, so you will recognize it again faster when you are searching the inked prints.

Use “Level 1” considerations, as well. If your latent print has thick, wide ridges, don’t waste your time trying to compare it to the inked prints of a person whose ridges are thin and close together. If your latent is about a six count left slope loop, don’t waste time on inked prints much more or less than six ridge counts in left slope loops. Likewise, if the latent whorl has an outer tracing, don’t waste time comparing it to whorls with meet or inner tracings. (If you don’t understand “ridge counts” or “whorl tracings,” get that little FBI “Science of Fingerprints” book back out and study your definitions some more.)

So, ANALYZE the latent print at several levels – find your target group and memorize it by drawing it on a sheet of scratch paper, then look at the pattern for general considerations.

Next, go to “COMPARISON.” Ashbaugh tells us that the comparison takes place in the brain, NOT in the eyeball. Therefore, if you have done a competent job of memorizing the latent print’s target group and pattern, you will recognize it again when you see it, even when you are not looking at the latent print at the time. Almost all senior level examiners can tell you stories about “recognizing” a fingerprint they haven’t seen in weeks or even months, so here is the key – memorize the target thoroughly and have faith that you will recognize it again when you see it a few minutes later. Once you have done that – memorized your target group – then put the latent print down and leave it down. Pick up the inked prints and start scanning the patterns. You are beginning the “Comparison” part of the process. You eliminate inked prints whose patterns do not closely match the pattern of the latent print and you do not waste time looking for the target group in them. When you come to an inked print with a pattern that does match the pattern of the latent, then (without picking the latent print back up) you look in the place where the target group should appear. If there is nothing there that even remotely resembles the target group you have recognized, then you move on to the next inked print without ever picking up the latent print.

You only pick up the latent print when you find an inked print with both the pattern and the target group that you are looking for. This takes you to the “EVALUATION” phase of the process. Now you can put the latent print down next to the inked print and put the magnifiers on them and go back and forth until you either identify or exclude the inked print as being the same as the latent.

Okay, here is a secret that I think a lot of people do not know. When you make an identification, eliminate that suspect from further consideration – at least, for now. In other words, each time you make an identification, remove the inked fingerprints AND the inked palm prints of that suspect from the stacks of inked prints. In this way, for the first latent print, you have a suspect pool of 15 suspects; for the second latent, you have 14 suspects; for the third latent, you have 13 suspects; and so on. In reality, there is NOT an exact one to one correspondence between all fifteen latents and all fifteen suspects, but early in the test, we will play like there is. When you make an identification, eliminate that suspect from further consideration. We’ll get back to this later.

Up to this point, we have assumed you will find that you will make the identification using that first target group you memorized. But this may not always be the case. If you have memorized your target group thoroughly and you and carefully searched through all fifteen of the suspects, do NOT continue to look for the same target group. Go back to the latent print and reanalyze it for a second target group.

Search your first target group very carefully, but search it through the stack of inked prints only ONCE – then forget about it and go back and find a second target group. Memorize the second target group thoroughly, then search it carefully ONE TIME through the inked prints, then forget it and go back and find a third target group. Memorize it thoroughly, and then search ONE TIME through the inked prints for it.

What I am trying to stress here is the ONE TIME concept. If you have memorized a target group thoroughly, you will recognize it instantly when you see it. If you search and do not find it, that means it does not look the same in the inked prints and if you keep looking over and over and over for the same target, you will keep missing it over and over and over. And that, my friend, is a waste of time – valuable time you do not have to waste on the test. So search a maximum of three target groups one time each. If you still haven’t found the identification, put that latent print at the bottom of the stack and move on to the next latent. You should never waste more than ten minutes on any latent print until you move on to the next latent. Search fast and NEVER get into a rut on one latent. If you allow that to happen, you might as well turn in the test unfinished and go home early. “Churn” those latent prints – search the first target, the second target, the third target, and put that latent to the bottom of the stack and move on to the next latent.

There is an added bonus of doing things this way. You may give up on a latent after those first three fast but thorough target group searches and put it to the bottom of the stack, only to spot the target group two or three latents further down in the stack before you even come back to that one you missed. Most senior examiners have had this happen on the work bench, as well.

So, search the first target, the second target, the third target, and move on to the next latent. When you make an identification, pull all the inked prints for that suspect.

Now, let me modify the “target group” idea when it comes to palm prints. In most palm prints you have a multitude of creases. Most of the time in palms, a group of creases make a better target for the initial search. Once you find the “crease target” in the initial search, then you go to the “points” in the comparison phase when you put the magnifiers on the prints. Sometimes, creases or wrinkles even make great targets in fingerprints, as well.

And while we are on the topic of a target other than a group of points, don’t overlook scars and warts that show up in a latent print, either. Those make some of the best targets of all. Another excellent target is an open field. In other words, if there is a field of parallel, unbroken ridges in the latent in which no ridge endings or bifurcations exist, that “open field” makes a great target.

To review the strategy for the comparisons as we have discussed it so far, separate the latent fingerprints from the latent palm prints and the inked fingerprints from the inked right palms and left palms. Organize the latent fingerprints from easiest to hardest, and the latent palm prints from easiest to hardest. Begin with the easiest latent fingerprint. Analyze it thoroughly, pick the target that will be easiest to find in the inked print, and memorize that target. If the target is a group of traditional “points,” draw that target to help memorize it. Compare latent fingers to inked fingers, latent right palms to inked right palms, and latent left palms to inked left palms. Compare the target group only once through the stack of inked prints and if you do not identify the latent, immediately go back and find a second target. Search the second target one time through the appropriate stack of inked prints. If you do not find the second target, go back to the latent and find a third target. Search it one time and if you do not find it, put the latent to the bottom of the stack of latents and move on to the next latent print. Do not keep searching the same target over and over, and do not cross-compare latents yet at this point (latent fingers to inked palm cards, right latent palms to left inked palms, etc.) When you make an identification, eliminate that suspect’s inked finger and palm prints from further comparisons. Then move on to the next latent. Search all of the latent fingerprints, then search all of the latent palm prints.

Now, when you come back to a latent print for the second time in the stack, hold it out and say to yourself, “Okay, what’s the trick here? Why did I miss it the first time? How can I look at this differently? Could it be a different area of skin than I thought?” There are some latent prints that are tricky. There may be a latent print that looks like a fingerprint that in reality is a palm print. Or there may be a latent print that you believe at first to be a palm print that turns out to be a fingerprint. Begin searching each latent as your first, best guess dictates, but do not get married to that idea. On the second search, be flexible and try to figure out if the latent could have come from somewhere else.

Using this strategy, you should be able to get at least 12 of the identifications without too much trouble. At some point, you will want to open the suspect list back up and include all 15 suspects’ finger and palm prints. But if you do this too soon, you will waste valuable time looking through inked prints that could not be the correct identification, so hold off until you are at a complete roadblock. Hopefully, you will have at least twelve identifications by then.

When you do reach a complete roadblock, or after 13 or 14 identifications, go ahead and bring all of the inked prints back into the stacks for comparison. By the time you get to searching a particular latent for the third or fourth time it has come up in the stack, you will probably want to search it against everything. There is not an exact one to one correlation for the latents; in other words, there may be a set of suspect inked prints for which there is no latent, or there may be two latents to the same suspect. But for the first two thirds or more of the comparisons, you will save time by comparing latent fingers only to inked fingers, and by eliminating suspects. But eventually, you may want to bring everything back in and compare to everything. DO NOT DO THIS TOO EARLY!


It is always helpful to prepare and take some practice comparison tests. To do this, you will need fifteen “volunteers.” Over the years, I have fingerprinted the other criminalists in the lab many times. I have also printed many of the patrol officers and investigators who have come into the lab to check on cases. In addition, I will frequently ask people taking a tour of the lab for prints (spouses and friends of other employees). I have even been known to snag people in the hall and ask if they can spare 20 minutes when I am desperate for a new set of prints.

Before you take the volunteer’s inked finger and palm prints, get them to deposit some latents for you. In that regard, you do not want people with too-clean hands. But just in case, keep a little hand lotion handy. Only a drop or two will do the trick. A big squirt of hand lotion will render the person’s latent prints too greasy and heavy and may even have a halo effect from the hand lotion, so go extremely light if you resort to hand lotion.

In the lab chemical room, I have a piece of clean plate glass (used to be the cover for the aquarium when that was how we superglued), on which I will ask the person to simply put both hands down flat with the fingers splayed. I also have a couple of coffee mugs, which I will ask them to pick up (not by the handle) as if they were just naturally taking a drink. Sometimes I use clean keys or clean coins, or test tubes or beakers, just to vary the background noise and distortion due to shapes of the surface.

Dust and lift 15 or 20 latent prints from each person, but do not lift too-easy latents. If a latent is too pretty, take your own finger, rub it on the side of your nose, and carefully smudge out a core or delta or easy part of the latent. Then redust the latent before you lift it. Lift a few easy latents, a bunch of medium difficult latents, and a few really nasty latents.

Then take inked finger and palm prints from the volunteer. I like to let them make up an alias name, although beware of cops and dispatchers – they sometimes tend to get a little vulgar. Or you can make up alias names yourself, or just assign numbers (Suspect 1, 2, 3, etc.) We have gone almost exclusively to the new water soluble fingerprint ink. The prints are not quite as crisp under magnification, but for the vast majority of people, the inked prints turn out very good. The advantage of using water soluble fingerprint ink is that your volunteer’s hands will come absolutely clean, even without soap. The older grease based fingerprint inks (printers’ ink) is impossible for some people to get completely clean from their cuticles.

After you have a stack of latent prints and inked finger and palm prints from at least 15 volunteers, you are ready to put together some practice tests. Take one latent from most people, but two latents from maybe one person. In selecting the latents, use maybe 8 or ten medium difficulty prints, a couple of slightly more difficult latents, and two or three pretty nasty latents. Also, use a variety of 9 or 10 fingerprints and 5 or 6 latent palm prints. Then use sets of inked prints that match all fifteen of the latents to 13 or 14 people, making up the difference to 15 sets of inked prints with “strangers.”

Number the fifteen latents 1 through 15 and put them into an envelope and label it “Test 1.” Put the fifteen suspects’ inked prints into another envelope and label it correspondingly. Quality photocopies work just as well as original inked prints, but not for the latents. For more authenticity, if you want to go to the trouble, scan all of the latents and all of the inked prints at 1200 PPI or greater and print them on photo quality paper, then take the practice tests using the printouts from the scanned images.

Ideally, somebody else would be able to put the practice tests together for you so you do not “know” any of the latents. But in my experience, but the time you get the tests finally assembled, you will not remember who any of the latents came from.

After you have several practice tests, you are ready to practice your “strategy.” My recommendation is to not practice too early. Apply for certification, get a test date, and then use the practice tests beginning 3 to 5 days before you actually take the certification test. Dump the latents out of their envelope and separate the latent fingers from the latent right palms and the latent left palms. Then dump out the inked prints from their envelope and separate the inked fingers from right palms and left palms. Put the latents in each stack in order from easiest to most difficult.

Begin with the easiest latent fingerprint. Find your target. Memorize it. Draw it (I cannot emphasize enough the value of drawing it.) Search it through the inked fingerprints one time only. If you find it, pull the fingerprints and the palm prints from that suspect. If you don’t find it, go back to the latent and memorize a second target. Search it only once. Then a third target. If you still haven’t made an identification, put that latent to the bottom of the stack and move on. Keep churning those latents. NEVER allow yourself to get into a rut on one latent. If you do, you can burn off an hour or more before you even know it, and on the real test you cannot afford to do that. So apply the strategy strictly on the practice tests. You want the strategy to become “habit” so it feels natural and you don’t have to think about it when you take the real test.


The fourth part of the Certification Test is the testimony portion. Check the IAI website, as referenced early in this article. If you have ever testified to a latent print identification, then a transcript of that testimony can be mailed to the Certification Board Secretary following the successful completion of the first three parts of the test. To get a copy of the transcript if you do not already have one, first ask the prosecutor. If a transcript was typed for an appeal, the prosecutor can get you a copy for free. If not, then if you remember the name of the case and the court in which you testified, you can contact the court reporter and ask for a copy of the transcript. The court reporter will charge a fee per page. A lengthy transcript can cost several hundred dollars (the last one I bought cost me over $400 and included a day and a half of testimony). There is always the possibility you can ask your department to pay for the cost of a transcript, both for study to improve your testimony and as part of your certification process.

If you have never testified to a latent print identification, the Latent Print Certification Committee in your state or region may be able to arrange a mock trial to satisfy the requirement. The IAI may also take a hypothetical transcript in which you type out all of the questions a prosecutor would ask and type the answers you would give. Check with your local certification committee to find out.


Customizing a strategy includes an honest self-assessment. If you believe you can make twelve sort of average identifications in five or six hours, take the pattern comparison and TFMC parts of the test first. Then do the comparisons and go for as many as you can get. Don’t be a quitter.

If you are afraid that twelve sort of average identifications would be almost impossible for you to complete in six hours, take the comparison part of the test first and quit the comparisons as soon as you get twelve. Then take the pattern interpretation and TFMC parts of the test.

When doing the comparison part of the test, begin by separating the latents into three stacks – fingers, right palms, and left palms. Separate the inked prints into three stacks, also. Put the latents in order from easiest to hardest in each of the three stacks. Start with the easiest.

Do a thorough “analysis” of the first latent fingerprint. Select and memorize the target in the latent that will be easiest to find in the inked prints. If the target is a group or cluster of points, DRAW the target.

Do each “comparison” by looking only at the inked prints to search for your target. Search the inked prints without putting the latent print down next to each inked print in turn and do not even look back continually at the latent. If you did a thorough “analysis” and memorized your target properly, you do not need to constantly refer to it. And if you do constantly look back at the latent or, worse, put it down next to each inked print to compare them, you are wasting a tremendous amount of valuable time in doing so.

Do each “evaluation” with the latent and inked prints side by side. When you make the identification, eliminate the suspect from further comparisons.

After you have made 13 or 14 identifications, open the suspect list back up and bring all the suspects back into the comparisons.

After you are through with the identifications, do your “verifications.” In this phase, I will warn you that most erroneous identifications test takers have scored on the test were not erroneous identifications at all. They were “clerical errors.” When you do your “verifications,” make absolutely certain each latent is marked correctly as to the finger, hand, and suspect name you identified it to. Check just as carefully for clerical errors as you normally do for ridge formations during “verification.” The clerical errors will be counted as erroneous identifications. Double check and triple check. Make absolutely sure you have them marked correctly.

Then turn in the completed test to your proctor, and GOOD LUCK!!!

For more information or to discuss this article, please feel free to call or email me:

Pat A.Wertheim
Arizona Department of Public Safety
Southern Regional Crime Laboratory
6401 S. Tucson Blvd.
Tucson, AZ 85706
Email: (if you email, please use the word “fingerprints” in the subject line or it may get deleted as spam).
Phone (work): 520-746-4570

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