Another Interesting Article

[Pat A. Wertheim]

Bill Bodziak emailed me an article and asked if it represents current thinking in the field of latent fingerprint examination. I gave Bill my response, but I wonder what other people think. Of particular interest might be the beginning sentence of a paragraph on page 7 of the article:

In conclusion, it is my "non-scientific" opinion that the Individualization of Fingerprint Evidence is not a Science in any way, shape, or form.

But read the whole article. What you think? Here's the link: http://www.4intel.com/images/fingerprints.pdf

[Gerald Clough]

Here we go again.

I don't think this one is ever going to be settled, but I will challenge the windmill and try. The rest of the technical community has never settled the issue for anything else but the limited case of unquestionably "pure" science. In that view, "science" is limited to those inquiries in which knowledge accumulates as a set of laws derived from arbitrary first principles and extended from those unprovable assumptions by defined processes that, barring error in applying the rules, are eventually agreed upon by all the adepts. There may be argument about the connection with the reality to which the knowledge is applied, or even inability to know if it applies in a useful way to any reality, but the question of whether or not it proceeds according to the rules can be absolutely settled. It is saved from the possibility of error in questions of whether it usefully applies to reality by all agreeing that any conclusion is subject to being shown to be wrong. Without that agreement, it deteriorates into mere dogma.

Now, a great deal of the work of scientists involves observation, nearly all of which is observed by methods that cannot be said to observe with total accuracy and confidence as to what is observed or what mechanism is being observed. The animal behaviorist accepts that his human perception and judgment of connection between observed events will not necessarily be those of another observer, not will his interpretations of connection and cause, the "meaning" if you will, find even one other in agreement. But without the observation and without the willingness to doubt, there can be no advancement of knowledge, and, in that field, Skinner would still be the authority.

But that doesn't answer the question of whether or not the behaviorist is a "scientist" or whether his work is "science." The "pure" scientist would hold that it is not. Others would hold that his observing is an art applied to gather what is needed to propose scientific principles to be explored. Others would include both as "doing science," the search for principles being doomed without the observation or would hold that the fact that there are some areas of inquiry that operate within closed systems of axioms in no way restricts the meaning of "science" to that minority of fields.

Part of this is a result of never-ending specialization. The farther back you look, the more general were the efforts of "scientists," originally operating under the title of philosopher. A scientist might comfortably work simultaneously in pure mathematics and in the more speculative fields in which the observations of physical phenomena was building the grounds upon which to even begin logical inquiry. And the often made significant contributions in multiple fields. A man might advance optics in order to observe microbes and then proceed to theorize on their natures and seek to test those theories.

My personal view is that an endeavor leaves the realm of science when it moves from seeking tentative conclusions with full acceptance that they may be completely wrong (no matter how hard one may fight to defend his proposed knowledge) to a seeking to settle the question of what the speaker can say with some arbitrarily high confidence from the evidence at hand - and that no further inquiry on his part can ever say more. It is not "science," because it he does not make a statement represented as something that can be, eventually, agreed upon as correct or incorrect by all the adepts. It is his individual conclusion that he would make in the face of any number of dissenters.

Okay. I can hear some howls. Some examiners have for too long held that any competent examiner with reach the same conclusion, or at least will not reach a conflicting conclusion. When challenged, the response may be that the conflicting conclusion reflects a lack of competence. This position is almost uniquely that of the forensic disciplines in which features presumed to be random are observed by humans. (Even DNA, to some extend, but DNA conclusions of identification are presented in a form not unlike a forecaster's chance of precipitation. They can't, barring malfeasance or technical fault, be wrong.) But, the latent print examiner can only opine as to the sufficiency of what he can observe to be powerfully arguable as likely to reveal the truth. It is only the fact that almost all conclusions are made about trivial issues that the illusion of universal agreement can be maintained.

It is, in fact I think, latent print examination's pronouncements of certainty and exclusive conclusion that prompts the heated criticism of it as non-science. Scientists say, "This is truth. I am prepared to defend it. Bring on the dissenters. They will see the light.", but the scientist argues hard because vigorous argument enforces the rigor that keeps scientific inquiry moving in a productive direction, rather than shooting off in all manner of tentative directions. He is a scientist exactly because he is open to being proven wrong, as he sought to prove others wrong. Latent print examination, at its best (and it's not always at its best) says, "I believe this to be the truth. I am prepared to defend it. Bring on the dissenters, but I shall not yield." Legal proceedings require that adversarial position. There must be differing opinions from which to choose. The fact that, for most of its history (and largely true today) latent print examination has produced no choice from which the judges of fact may choose invites the critical comparison with science.

It is my opinion that latent print examination is not and cannot be science, exactly because it is a forensic discipline, and it is a forensic discipline because it is not a science the conclusions of which can be universally agreed upon by an extension of knowledge. Argument between "art" and "science" is incorrect. The correct issue is not a question of process. It is a question of purpose.

[Pat A. Wertheim]

Dear Gerald, not "Here we go again," but "Here we go still." I suspect this debate has been ongoing for a century without pause and will continue another century at least. Is that a bad thing? I think not. I believe it should go on unabated. As you point out, we work in an adversarial system. Of more importance than to which side of the argument a specific examiner subscribes is the fact that only through continued debate can that specific examiner understand his/her position and defend that position in an adversarial system. Arguments shift over time. The defense attacks in vogue when you and I began in the 1970's have shifted again and again and some have come full circle. We have refined the answers we gave in the 1970's to suit the evolving arguments. Regardless of whether you are testifying for the prosecution or the defense, you must be able to defend your position. That is the nature of our business. Is it science? Not, as you point out, in the "pure" sense. But I believe we are playing a game of semantics and definitions. That is not altogether unexpected, for that is the game attorneys play and we present our conclusions in their venue -- the courtroom.

If it is a game of semantics and definitions, what is the definition of science? I tried to answer this in the public library in the late 1990's when I was trying to come up with a precise definition for an article I was writing for Fingerprint Whorld. What I learned in the library is that no two authors of science texts agree completely. They define exact sciences and descriptive sciences. But we also talk about applied sciences and, as a subset, forensic sciences. In the article I wrote, I presented what I proposed is a scientific formula to explain how we make an identification. I equated it to ACE-V, which some courts have accepted as science. Whether it is science or not depends on how strictly you want to define "science." I accept there are pure or exact sciences. But I also maintain that applied science is still science, and forensic science is still science.

I think no one would argue over whether mathematics is science. Some consider it the only exact science. If you agree that math is science, would balancing your checkbook be science? Would it be the practical application of science, i.e., applied science? Would it be scientific in any sense? Some mathematicians have more talent than others. Some people are better at balancing their checkbooks than others. A mistake in your check register does not make mathematics unscientific. Some would argue that there are no errors in mathematics itself, only careless applications of the science by people who err. That is the same argument we hear from those who say that ACE-V correctly applied is without error. They proclaim that errors result from careless application of ACE-V and are human errors only, not errors of the methodology. Critics argue that you cannot separate error of the methodology from error of the practitioner. I am not completely convinced of the argument that the two cannot be separated, but I do know that if you are sitting in prison because of an error, it matters little whether the error was in the methodology or was that of the examiner.

I will go on defending fingerprint examination as science, included in the subset of forensic sciences, which are in turn a subset of applied sciences. Call it my philosophy, which I believe falls within the purview of "arts" rather than that of "sciences" in today’s delineation of the two as separate and distinct. But I agree with you that they cannot be separated. Arts and Sciences have overlaps throughout the various disciplines and one could even argue they may be the same thing. Was Leonardo an artist or a scientist?

Thanks, Gerald, for your very articulate post. Let's keep the debate going. Otherwise, the newbies won't have a clue about the arguments and even we old timers may get caught off guard by some bright new attorney sitting at the table of opposing counsel. Now, if you will excuse me, I have to go balance my checkbook.

[Les Bush]

Hi Gerald,

Once again a very articulate posting on your thoughts culminating with your view that latent fingerprint identification is not a science. From that position it would be reasonable to assume you believe the whole of our knowledge about how fingerprints establish personal identification is also not a science. The principles for fingerprint science are the uniqueness and permanence of the friction ridge details. As Pat has said our 'newbees' need to know the difference between contemporary thinking and dogma. Since you have a strong view that latent fingerprint identification is not a science then you may be able to enlighten me on how friction ridges form pre-natal and in particular the primary ridges. My view has become one that the biological development establishes an interaction of nerve and skin tissues so that the whole skin functions as a tactile and effective barrier. I look forward to your views on the development of the primary ridges. Regards from oz. Les

[Big Wullie]

If fingerprinting is a science then how can so many be in total disagreement with each other ?

How can so many people end up wrongly convicted ?

As a mere Layperson interested in many cases of the past, Shirley McKie's in particular which also led to David Asbury being released too after being convicted, I find it very hard to understand exactly how differences of opinions originate in any case.

If a fingerprint cannot change then how can two So Called Scientists have different opinions ?

How can Peter Swann say Y7 is a left thumb print when others claim it was a right?

How can some say it was Shirley's and others say different ?

Surely this points to fingerprinting not being a science because any scientific opinion must always come to the same conclusion no matter what methods are used.

Fornsic scientists use chemicals to come to their conclusions, What do fingerprint experts use apart from powder and tape to lift the prints ?
When two scientist perform the same test they must get the same result, must they not ? so why then in fingerprints do we have so many experts in disagreement with each other ?

I believe in fingerprint evidence for the avoidance of any doubt, It is the way it is presented I am not comfortable with.

Anyone who stands up in court without scientific evidence to back up their claims in my opinion are merely just voicing their Opinion.

[Gerald Clough]

Les,

I take the question of science or not to be one that asks about what latent print examiners do, or rather, what latent print examination is for. We gain much from research that proceeds with the primary purpose of extending knowledge of the physical world. I doubt the various researchers delving into the formation of skin ridges have much specific idea of the problems to which the findings would be applied. For latent print examiners it confirms with description of a physical process what we assumed. The assumptions were correct largely because those who spend a lot of time looking at and thinking about such skin ridges concluded they were formed by a process whose specifics they could not know but whose nature seemed apparent. That research is, I think all would agree, science, scientific inquiry of a rather pure sort. That it was conducted my those who were primarily working on physiological development is to be expected for very practical reasons, but it could have been conducted by anyone with the intellectual background and resources. What made is "science" was its purpose, the nature of the pronouncements of conclusions and the fact that any such conclusions in "science" are really invitations to further research. That is the nature of scientific research - that it opens the door to more knowledge.

I would argue that no application of scientific knowledge to practical matters can be anything but wedded to the tentative character of the knowledge upon which it is based. The application succeeds to the extent that it produces results useful to the particular endeavor it furthers. That may be that the bridge stands up to its design load or that the pacemaker triggers at a point in passage of the electro-chemical signal through the heart's conduction system. In the case of fingerprint identification, the application succeeds in that it produces a conclusion of sufficiently arguable credibility that it is fit to be considered in important matters of law. Each conclusion is and end product, a termination of that individual inquiry. Nothing more is forthcoming or expected. Just as that particular bridge can be redesigned but will not do more than it was intended to do, which was to pass a stated load over thin air.

Knowledge of the nature of friction ridge development provides a highly convincing insight into how they form. While it confirms what was believed as to the nature of the development, it does not provide any absolute information about likelihood that some arbitrary level of uniqueness exists. It merely argues strongly that the likelihood of indistinguishable features drops as the quantity of usable impression increases. I personally guess that the research reveals a process whose nature is such that quantification is not a practical goal.

So, you presume incorrectly that I hold that knowledge applied in latent print examination is not "scientific" knowledge. What I argue is that latent print examinations are not undertaken as scientific inquiry, because their conclusions are presented as fixed opinions which do not admit to being upended by further investigation. And that is, because of their purpose, exactly how it must be. Were an examiner to take on the role of "doing science" in examinations, the examiner would be concluding with the purpose of preparing knowledge of that particular thing being examined to be challenged and perhaps corrected by the next examiner. Examiners are not, in their examinations, doing research. They are expertly producing a truth they can sponsor that will, once heard by those who will judge credibility, be accepted or rejected. But it is a conclusion that they do not intend to yield, no matter what may be concluded by an expert dissenter. It is therefore not the conclusion of scientific study. This is not to say that the examiner may then turn his attention and labor toward producing a genuine contribution to scientific knowledge. But that it another process with another purpose. Neither does the fact that the scientist in another field provides expert forensic conclusions cast him from the community of scientists.

So, my view is that the question of science of not is largely wasted argument, except that it may, through critical thinking, clarify the differences between the nature of two sorts of inquiry. "Doing science" is a particular thing. Doing latent print examination is not that thing.

[Charles Parker]

In commenting on the article by Ashton titled “Fingerprint Identifications (science or not) I think it is interesting only from the point that here is a senior LPE whose view point is that the very act of comparing a latent print is not a scientific endeavor and also that he refers to ACE-V as a “scientific methodology” and not “The Scientific Method”, although he does use the word “hypothesis” in the verification stage (p.7) which is a key component in the TSM. Other than those two statements most of his article displays the same general rhetoric that is postulated as the mainstream of Friction Ridge Analysis. Overall I like his article in that he makes a number of other statements that certainly clarify some issues. His statements in the 5th and 6th paragraph of page 5 are very articulate and from my point of view are “dead on”. I am especially impressed by his statement that “Intrinsic details with extremely rare features are given a greater individualizing power than those considered to be mundane or pedestrian”. Although such a statement warms my heart it is by no means mainstream with those distinguished members of the organization who set the standards for this discipline.

Overall a good piece of writing. Something to save and put in my library.

As stated the act of friction ridge examination is either “Art” or “Science” is probably as old as the discipline itself. Although those individuals who touted it as an art a number of years ago have softened their statement by saying “it is both----based upon science but the interpretation is more artful”. A statement I reject. The argument of Art or Science in my opinion is basically flawed. The argument presupposes that a person must pick one or the other, just like the CTS Proficiency in that you must pick ID or No ID, or some “scientific” studies that require a “is it” or “is it not”. For the argument on Art or Science why must the selection be one or the other? Is their another descriptive term that could describes the process?

In FRE 702 for expert testimony it states scientific or technical. While Daubert put forth the criteria for scientific testimony, Kuhmo added technical expertise into the Daubert criteria. So now we have three choices in that is friction ridge examination an art, technical or scientific process. Are there any other descriptive words that might describe the process?

Another word that comes to my mind is one that is used very often in this discipline. It is used in the title of a popular book by the name of “Qualitative-Quantitative Friction Ridge Analysis”. It is the first phase of the popular comparative model (methodology if you prefer) ACE-V. It is used in a number of other disciplines such as Questioned Documents, Firearms Identification, Shoe and Tire Print Analysis, Drug Analysis (Quantitative Analysis). If you have not guessed by now that word is “Analysis”.

So now we have four choices for a description of the very human action of comparing two friction ridge images to determine if they represent single or different sources! Is the process Artistic, Technical, Analytical, or Scientific.

Of course it is dependent upon your definition of each. I cannot tell you which definition to choose as that should come from reading a number of presentations and not just those that you might agree with but those that you may not. I have stated on this board before my definitions of each so I will not bore you with repeating them.

The second issue I would like to address and I have to do it very carefully is the statement that we are playing a game of semantics and definitions. I have heard it stated that we are just playing with words or it is just philosophical BS or defining concepts to suit your own agenda. In my point of view we are not playing a game. Words and concepts are what move a people or a discipline to a better understanding of the concepts and principals that govern that society or discipline. When a person testifies in court and another expert testifies somewhat semantically different it can add confusion to the court and the jury. We need to strive for a consensus in the terms we use. Imagine for a minute if we were to take the word “Plain Arch” which is a standard term which everyone should understand and start calling it a “Curved Arch” or a “Less Than Tented Pattern”, it would be hard for some of us to picture it while the name “Plain Arch” is plainly understood. I put to you the possibility that semantics could cause a guilty person to escape justice just a much as error can cause the wrong person to wind up in jail.

I agree that debate is needed but an open debate and open to all those who choose to partake of it and that no ones idea is ridiculed or other concepts are thrown aside. Ideas and concepts need to be discussed and considered until a consensus is reached by the discipline.

The question was asked “Was Leonardo an artist or a scientist”? Now it has been said that I am semantically challenged or that I am pedantic. The question as posed forces the reader to make a choice: one or the other. Is there another answer that could be more accurate? Perhaps if the question was phrased as “Was Leonardo an artist and/or a scientist”? The answer is quite evident from reading about his life. He was both. Not uncommon for his time or even today. Was Benjamin Franklin a writer and/or an inventor? Easy answer; he was both. When someone asks you a question in which only lists two possibilities then you need to consider the question very carefully. If you think that I am only playing with semantics or being pedantic, then just chalk it up to a character flaw of mine and move on.

As usual I want to thank Pat for the interesting article and his and Gerald’s position on this concept of friction ridge analysis. Please keep the debate going as I consider it interesting and a learning experience. Now, if you will excuse me, I have to go analyze my bank statement to determine who made the error in the account balance; my wife or the bank.

[Dogma]

Science: The investigation of natural phenomena through observation, theoretical explanation, and experimentation, or the knowledge produced by such investigation. Science makes use of the scientific method, which includes the careful observation of natural phenomena, the formulation of a hypothesis, the conducting of one or more experiments to test the hypothesis, and the drawing of a conclusion that confirms or modifies the hypothesis. (The American Heritage® Science Dictionary)

The science of fingerprinting is the observation and recording of dermal ridge patterns and features and the effort to understand their development, purpose and relationship with like features, an extension of biology.

A principle of fingerprint science is that dermal ridge patterns and features never change absent disease or some type of physical intervention.

The theory behind fingerprint science is that no two people will ever have the exact same arrangement of dermal ridge features within a certain but un-enumerated threshold.

Just because something is scientific, doesn’t mean that it is infallible. Quite the contrary. Fingerprint identification has come under fire because of claims of infallibility. Scientists interpret data differently all the time. It is only when a preponderance of opinion is achieved or error revealed that principles and theories are established or discounted.

Is it fair to say that the practice of medicine is not a scientific pursuit because physicians misdiagnose ailments based on the observation of symptoms and testing of patients? Is astro-physics not a science because some disagree with Stephen Hawking’s work on black holes?

Some seem to be saying that the application or practice of a procedure, though based on a scientific theory or principle, is not itself science. So, discovering the cure for a disease is science. Vaccination against the disease or prescribing a therapy to cure the disease is not. If we are to accept this premise then there is no such thing as forensic science. No crime lab achieves the actual discovery of the underlying theories which allow them to examine evidence and draw conclusions based on test results (disallowing for those that may conduct research).

But I submit that each forensic exam is in and of itself a scientific experiment. For in each exam we have unknowns, observable phenomena, hypotheses about outcome, testing of hypotheses, results leading to conclusions and testing of the process for repeatability.

When it comes to fingerprint comparisons, some are confused because the data used for analysis stays with the specimen and is never recorded abstractly as in a printout. But the same holds true for all of the comparative disciplines.

We can acknowledge that some examiners do not approach their work in a scientific mindset. To them the task is more like a puzzle: find the right pieces and the chore is done. Some would prefer to forget about all this science stuff and just see themselves as skilled operators completing a technical task. And, yes, there are still some left, just count up enough points and call it a match because "that’s the way I was taught." It’s strictly a numbers game.

The observation, measuring, quantifying and comparing of phenomena and the effort to hypothesize and test is most definitely a scientific pursuit.

[Les Bush]

Thanks Gerald,

Another interesting posting which in turn brought comment from Dogma about the structure of an applied scientific discipline. The reason I was asking about the primary ridge development is that it underpins the principles of permanence and uniqueness. The study of the friction skin process is the scientific knowledge from which we can then apply our technique (sequence, spatial, appearance) using the method (ACEV) and conclude (sufficiency or not, attribution or not). That is a pretty simplistic model by which we meet general scientific standards. I hold that our parent grouping in science is the criminalistic community and our application is forensic science.

To answer Wullie's layperson question as to how accurate is the application process this falls into the question of what is being done about standardisation? Without a philosophy of what constitutes our scientific knowledge, and without a model by which it is consistently applied and without some means of regulation of a standard of quality then the science of fingerprint identification is still (vulnerable?) such as the question about latent Y7 source attribution. Hope exists Wullie through groups such as SWGFAST and the European conference under Interpol. We will get to the bottom of Y7 and in some way we will reach a consensus about what constitutes our science. Cheers from oz. Les

[Gerald Clough]

Charles' reference to "analysis" returns me to my distinction between the purposes and conclusions of "science" and what we can call "analysis." For example, the science of chemistry makes possible the analysis of compounds. Scientific research gives us the knowledge of the structures and natures of compounds and extends that knowledge to discover chemical interactions and methods of analysis that we may apply to reach conclusions in questions of quantity and quality. Along the road to the knowledge we apply in the analysis lie theories proposed from prior knowledge and some inquiries that are false trails and some that are confirmed and move us to the next level of knowledge. When the scientific knowledge is sufficiently matured, the analytical techniques based upon it become sufficiently reliable form the conclusions to be considered by those who pose the questions.

And therein lies, I think, the distinction between the two labors, and my point is that analysis, as an application of scientific knowledge which has passed review and replication to such an extent that it is generally accepted, has a higher status as a measure of practical fact than knowledge that is, we might say, still under development. I think that missing that distinction is behind the errors I see in some legal argument over the reliability of latent print examination. I would argue that fingerprint identification represents analysis grounded, to the extent that it depends on such knowledge, in scientific conclusions about physiology about which there is no dissent about anything that matters much. That knowledge appears sufficiently well established that it has been elevated from a tentative finding to a finding that may be depended upon by those who will seek to add to it. The next researcher may depend on current knowledge of friction ridge development in seeking deeper information.

Analysis, therefore, has left the realm of research and is now an application of some knowledge that has passed beyond reasonable dissent. Its conclusions, therefore, may not reasonably be questioned by arguing that the underlying scientific knowledge is in question. Analysis may be relied upon exactly because it is no longer "science" and so it is no longer subject to the required caveat that scientific knowledge must always be questioned. The analyst may rely upon sufficiently established scientific knowledge but is not responsible for providing his own independent defense of that knowledge. He is a customer of "science." It is this that allows the analyst to pronounce immutable conclusions. To equate the analysis with scientific research, the "doing science," is to render the results of analysis as tentative and open to an invitation to challenge and a willingness give up the conclusion as must be the conclusions of research. The analysis, to be "doing science" would have to qualify each conclusion only useful until superseded by another analysis, and that is decidedly not as it is supposed to be. I differ from Dogma's assessment of a latent print examination as an experiment. It does not become so by borrowing terminology from science. I object, in fact, to the adoption of hypothesis. No hypothesis is required. The analysis will conclude with result, not confirmation or prior hypothesis. But my strongest objection remains with the nature of the conclusion.

This is not to say that "science" is wholly barred from the arena. The distinction is often not sharply drawn. In some fields, the underlying scientific knowledge may be essentially unassailable, but the question of whether it is properly applied in an analysis may call for testimony from the scientist who possesses the ability to step the chain back to first principles and to, in effect, certify the analytical technique. Having passed that test, an analyst who cannot independently validate the science may credibly present the results of analysis. And the scientist may be called back into the contest, should someone offer a novel challenge to the validity of the scientific basis.

So my position is that, for the purpose for which it is conducted, latent print examination, the analysis, is more compelling than any argument limited to developing scientific knowledge. "Doing science" is a rigidly controlled activity, strictly limited to forging links in a chain composed of nothing but other scientific knowledge acquired under the same constraints. Were we to limit questions of fingerprint identification to strict science, we would have little to offer. But, because the existence of physical evidence of this sort is generally agreed to contain information potentially useful in settling issues in which we are bound to bring to bear all reasonable means of settlement, we are called upon to argue from the best of human experience and what scientific fact is known and to offer conclusions of a proposed truth that we believe so reliable that we frankly state them without qualification or reservation.

We are not bound by "science" to hypothesis and tentative demonstration of proof that admits nothing not scientifically proven. We are called upon to state what we believe from some science and a vast experience of observation and considerable body of verification of conclusions. It is that component of practical expertise that makes out analysis vastly more useful than the stark limits of "science" to those things concluded strictly from the chain of science. The most knowledge about scientist, limited to his scientific knowledge, can conclude little about fingerprints than how they form. The expert analyst can help us decide questions of fact.

We are blessed with our range of experience and knowledge beyond that of science, and it is therefore inescapable that we will depend upon things that cannot be established to the satisfaction of undiluted science. We cannot escape dissent by retreat to the position of science without becoming impotent in the realm of practical application, anymore than science can advance by admitting human experience as scientific proof. Our arguments must be those that compel belief to whatever degree is required, according to the arena in which we testify, not by a scientifically testable chain of scientifically certified knowledge, but by all our powers and experience.

Through all this, we are, I think, stuck with forensic "science" and must bear that burden as best we can.

I would answer Wullie that matters of fact in law are not resolved by "science." If they were, only some intolerably few could ever be resolved, and we could dispense with courts, judges, juries, and advocates and throw ourselves on the mercies of scientists who would most often answer, "We don't know." There will therefore be, even aside from process errors, some conclusions of forensic analysis that may be argued by honest and competent analysts. The number of these subject to reasonable dissent are very, very few, such is the high standard demanded by the triers. The overwhelming majority of analytical conclusions suffer no reasonably debate. They are based on such a quantity of material subject to the analysis that almost any imaginable error in observation or interpretation cannot begin to affect the essential conclusion. And, in systems in which a high standard of performance is required of analysts and in which elaborate mechanisms of review are lavishly provided, the number of persons wrongly convicted and not ultimately exonerated is extraordinarily small. And strive as we might for zero, that laudable goal is impossible, rather like the Zen gardener's commitment to lifelong improvement with no expectation of completion. Here, the goal is ever more useful expert opinion, not ultimate absolute certainty. It cannot be otherwise.

[sharon cook]

One of the problems I see with this debate is the underlying principle that "All scientists agree with each other." Therefore latent print analysis can't be scientific because there are disagreements. That's garbage. Scientists disagree on just about everything! That's what keeps "science" such a dynamic process.

[Gerald Clough]

After a while, your head begins to spin, and you start to hallucinate and begin asking if the question of whether or not latent print examination is science or not can be decided by science. There's probably some kind of uncertainty principle at work here that the scientific nature of a process cannot be established by a scientific process. Therefore, we all get to argue our own analysis of the question.

But to respond to Sharon's comment. In the process of developing scientific knowledge, scientists must be prepared to disagree, challenge proofs, and accept when superior proofs are given. They may argue for a long time or a short time before one or another notion achieves general acceptance and the line of inquiry takes that road. But so long as they are arguing and general acceptance has not happened, few of those contested notions become credible enough to become factors in forensic analysis. Nevertheless, useful analysis can proceed without every factor being a generally accepted bit of scientifically validated knowledge.

[Dogma]

What seems to be forgotten is the purpose of our endeavors. It does not matter what scientists think of fingerprints. It does not matter what academia thinks of fingerprints. What matters is what the courts think of fingerprints. Legal matters don’t always line up with popular or specialized discourse. What means one thing in court may appear alien to its meaning among the general populace. This is where the Habers and Coles falter. They try to convince the court to adopt meanings that may be common in their realm but are outside the world of the judicial process. Judges don’t concern themselves with the abstraction of science. They are only interested in the practice of examinations based on a sound body of knowledge using procedures which are accepted by the pertinent professional discipline and whose results can be verified. And that, my friends, like it or not, is called forensic science. In court, science is seen not only as the underlying basis for testing but the actual testing itself.

[Gerald Clough]

What matters is what the courts think of fingerprints. Legal matters don’t always line up with popular or specialized discourse. What means one thing in court may appear alien to its meaning among the general populace. This is where the Habers and Coles falter.

Exactly. And that is why they don't make it into testimony as to their opinion. The possess all the applicable science. They lack the relevant experience and acquisition of the components that fall outside generally accepted scientific fact but that fall well within the components generally accepted by adept analysts. They make true statements of scientific fact in objecting that the conclusions are not obtained by strict science, but the courts recognize that all useful practical analysis need not be and most off is something else.

[Les Bush]

Hi again Gerald, last time for me,

Having distilled your post I get the picture your view of latent fingeprint identification as a science is based on the practice of analysis by the expert. The knowledge an expert has is given that fingerprints are unique and the challenge is finding that uniqueness within the friction ridge details of exemplar and latent. My view about the ability of an expert is not a scientific one but rather about the discipline of following a set or rules (technique/method/conclusions). The pure science for fingerprints is a biology issue about how skin comes to be unique and is then reproduced/repeated in both the exemplar and latent. The ability of experts to conduct examinations is fundamentally unchanged (spatial, sequential, appearance and sufficiency) but the knowledge we have of how fingerprints are unique is quite substantial and growing. As Ive said in my latest paper the principles of the permanence and uniqueness of friction ridge skin are truly understood when connected with their evolutionary and biological origins. With this view we become a science that is relient on natural laws/processes governing the human body. As scientists of friction skin development we are experts in recognising patterns of unique friction ridge detail. Regards from oz. les