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G o o d   M o r n i n g !
Monday, September 27, 2004

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

Prints Link Trio to Lots of Pot   UNION DEMOCRAT, CA  - Sept. 24, 2004 ...through the fingerprints officers lifted off items left at the scene, the suspects were tracked down...

Fingerprints on File, Right From the Patrol Car   NEW YORK TIMES, NY - Sept. 23, 2004 ...high-speed wireless communications could become widely available to officers in the field, not just those back at headquarters...

Police Fingerprint Plan Draws Fire TORONTO SUN, CANADA - Sept. 21, 2004 ...proposed changes that would let Toronto police keep fingerprints of people charged but not convicted of certain crimes...

Print Case 'Shames Scots Justice' BBC NEWS, UK  - Sept. 20, 2004 ..."Scotland's fingerprinting agency has become a worldwide embarrassment," according to an expert...

Last week
we looked at latent print sufficiency as a three-tiered structure; sufficient for case evidence, sufficient for comparison, and sufficient for individualization.  We defined the differences between each tier and saw that at each one of these levels it is possible for latent prints to drop off, or not be sufficient for the next level.

This week

we further explore and clarify additional points on this subject.
Re: Latent Print Sufficiency
by Tom Adair

I'm curious about something Mr. Wertheim, if we follow your argument to it's logical conclusion then doesn't it at least suggest that a crime scene analyst or latent examiner should process every possible surface in a crime scene for latent fingerprint evidence? Shouldn't finger marks, with no ridge detail, be collected or swabbed for possible DNA evidence? If a latent impression has one or two ridges with level three detail present over a very small surface area shouldn't that be collected as well for review? In a robbery of a public business (like a fast food restaurant) shouldn't everything in the restaurant (including trash) be collected for possible analysis and comparison by "any" examiner who argues it might contain "valuable" evidence? If the fingerprint examiner doesn't process every possible surface then aren't they doing an "injustice" to the system? After all, failure to collect evidence that may be used to defend or exonerate a person in court would be wrong, correct (see third quote)? What about not using every method (i.e. chemical reagents, fluorescent powders, Lasers or ALS) possible to develop prints at a crime scene or on evidence? If a crime scene investigator only uses black powder, aren't they potentially missing evidence that could be "meaningful" to "any" other analyst? How do you view our responsibility to the criminal justice system? Are we to investigate every possible theory or are we to conduct a reasonable analysis and make reasonable decisions? I've copied a couple of quotes from your article and while they may be somewhat out of context the underlying message I get is the argument I've described above.

"Is it possible that ANY determination could be made from this impression by ANY person"

"What if a DNA analyst determined that they couldn't deal with mitochondrial DNA, so they didn't preserve a piece of hair evidence?"

"What I am ready to do is uphold my responsibility to the criminal justice system and preserve evidence that may be valuable in a criminal case. To do otherwise with a latent impression when the possibility does exist (however small) for another examiner to arrive at any conclusion, reeks of egotism and injustice."

I obviously have concerns with some of what you are saying. As a fingerprint examiner and crime scene investigator I don't believe justice is served by us becoming garbage collectors (that is to say collecting every item in a scene because "any" other examiner "might" argue it is relevant in some way). In doing so, I think the criminal justice system would creep at an even slower pace than the pathetic state it is in. In my humble opinion, I believe it is the job of the analyst to make reasonable decisions about the evidence they encounter at crime scenes. I prefer to analyze a scene to determine what evidence may be of probative value to the investigation. This means making decisions about what evidence will be meaningful for a court and the investigation as a whole. Evaluating a very poor impression to conclude that a particular person could not have made that impression may not assist the courts in drawing any meaningful conclusions. For example, if a poor quality print (one that is of very small area and contains only level one detail) could be used to determine that the defendant did not make that particular impression, what does that tell us in our holistic analysis (how does it look through the wide angle lens?)? Does it mean that the person in question was not there? Does it mean that they did commit some illegal act? Does it mean someone else committed the act? The answer to all three would be no, in my opinion. What value does that impression hold if it can not be identified? It's only value is to eliminate a particular person from making that specific mark. Now obviously, if that mark happens to be developed in an area that has significant meaning in the investigation (such as a weapon or a point of entry) then it's value may increase and investigators may weigh the value of it more heavily. I don't know of any of my colleagues who would not document even a poor impression in an area like this. But that's not what we're talking about, I don't think. We're talking about ANY print ANYWHERE that ANY other analyst could argue it MAY have ANY meaning.

Obviously, the evidence collected by most crime scene investigators is evaluated for presentation in court. If a fingerprint (or any other item of evidence) is not collected then it can not be used against a defendant. One might then argue that the point is that other evidence (or fingerprints) might support the argument of excluding a particular defendant from committing a crime. But then, haven't we have gone back to the original argument of "collect everything" because it may be of value. Ultimately, it is up to the lawyers to argue what should or should not have been collected, and juries or judges must weigh the arguments. Most agencies simply do not have the resources to collect or process every item found at a crime scene. Processing crime scenes and evidence is about making choices. Sometimes we make the right ones, sometimes we make mistakes (or so it's argued). I wholeheartedly agree that reports should be written in a way to fully document the analysis, however, at crime scenes, there are some impressions I simply do not collect due to their very poor quality. There are also areas of crime scenes I simply do not search for latent fingerprints, depending on the evidence present, witness statements, and my experience and training.

Perhaps I have misunderstood your position and if so I'm truly sorry. I'm sure that I'm off track of the discussion regarding "latent print sufficiency" as it was probably intended. I value much of what you bring to these discussions and your voice is a welcome sound in the choir. I make these comments, not simply to argue a point, but to engage you in a discussion to better clarify your position to me. Also, I think my points are something we should consider when engaging in this discussion. What is the responsibility of the crime scene analyst at the crime scene? If you care to, I would greatly appreciate your thoughts on my comments.

Respectfully submitted,

Tom Adair
Senior Criminalist
Westminster Police Department
Westminster, CO



Thank you for your well thought out and lengthy response.

A portion of your message encapsulates an example I gave within the Detail... that just because a difficult impression is capable of being excluded does not mean the suspect didn't touch the item or commit the crime.

The reason I "went there" with this week's Detail is to get people talking about this subject. This is the direction that many ASCLD-LAB inspectors are going, and if you have anything in your policy and procedure about documenting the sufficiency of latent prints, they may take it to mean sufficiency for anything by anybody, and you might get "dinged" for not having done this. If you don't have "sufficiency" defined, then it's up to them.

I have heard talk throughout the last year about requiring preservation of all ridge detail. I had hoped these rumblings would go away, but they have not.

I also agree with your main point... there comes a point where collection becomes impractical. But who decides this? The analyst does. In your case, it sounds as if you are the analyst and the examiner. The Detail was not written for you... it was written for those who do not have examiners in your position.

As a latent print examiner, I would much rather be the judge of impressions than the crime scene technician not trained in latent print analysis. I would rather sift through 12 latent lifts and only mark 1 latent print of value than to not have anything at all to look at. That was the intent of my message.

As for setting the threshold, it also operates on the collection end of things. Sure, you could spend 2 days completely processing a burglary scene. But it isn't practical. I recognize that... I'm talking about impressions that ARE at prominent places in the scene. Who is to say the smudge at the POE is not worth lifting? The latent print examiner with a magnifier and good lighting, that's who. And most times, that person isn't at the scene... so I'm saying go ahead and lift it for later.

Discussion is good!


Discussion Points:

In what situation(s) is it acceptable for CSA's who are not trained to competency in latent print examination leave ridge detail at a crime scene uncollected?

Do you feel it is acceptable as a latent print examiner to not conduct a complete comparison of a small area of ridge detail because of the real-life constraints of agency budget/time shortages?  If so, who should set that threshold? (you or the agency?)

Do you feel it is ironic that we are talking about documenting and keeping more when budgets and time for cases seem to be less?

To discuss this Detail, the message board is always open: (

More formal latent print discussions are available at (


Surefire ways to tame stress

There's never enough time.  Reports are due.  Project deadlines are looming.  Stress is closing in on all of us.  You can't make stress go away completely, but you can use these tips to remove some of the edge:

1. Replace the phrase "I have to" with "I get to."  Even the most onerous tasks seem easier and less stressful if you get to do them.  By removing the feeling that you have to do something, you've reduced some pressure and stress.

2. Write down your thoughts when you're in a stressful situation.  After you're done, you can crumple up the paper and throw it away.

3. Tackle the most stressful tasks first.  As the day wears on, we become tired and our stress defenses lag.  So it's best to handle the most stressful events early in your day when your body is most alert and rested.

Adapted from "Twelve Tips to Reduce Stress," via Communication Briefings, February 2004,



Updated the Detail Archives


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Have a GREAT week!