LATENT FINGERPRINT IDENTIFICATION IS UNRELIABLE AND FAILS TO MEET THE MOST BASIC SCIENTIFIC PRINCIPLES TO ENSURE RELIABILITY
A latent fingerprint is the reproduction of the friction ridges of the fingers in perspiration or oily matter on an object which has
been touched. See Gary W. Jones, Courtroom Testimony For the Fingerprint Expert. Latent fingerprint examiners make
identifications when they find a certain number of ridge characteristics to be in common, both in terms of type and location.
However, there is no consensus in the latent print expert community as to how many common characteristics should be found
before an identification is proclaimed. See An Analysis of Standards in Fingerprint Identification, FBI L. Enforcement Bull, June
1972.
A. Fingerprints are not as unique as once thought.
The long held belief that no to prints are alike has come under intense scrutiny in recent years. During expert testimony in a recent federal case, the government call Steven Karasky, a board certified member of the International Association for Identification (IAI) and a United States Postal Inspector. Mr. Karasky acknowledged during his testimony that no published studies regarding false identification had ever been conducted. He also testified he personally knew of instances where prints from two different people contained as many as ten matching ridge characteristics. See U.S. v. Parks (C.D. Cal. 1999). Following an evidentiary hearing the Court held that fingerprint evidence was not scientific and lacked sufficient indicia of reliability. In fact the Court was incredulous telling one of the experts: “You don’t have any standards, As far as I can tell, you have no standards, its just an ipse dixit.” The testimony was excluded. . See U.S. v. Parks (C.D. Cal. 1999) . See also The Challenge of Fingerprint Comparison Opinions in the Defense of a Criminally Charged Client Mears, Michael and Day, Therese M 19 Ga. St. U. L. Rev. 705.
In addition to United States experts recognizing the lack of total uniqueness in latent prints, experts in other countries have discovered the same and published their research. Israeli fingerprint examiners found fingerprints from two different people that contained seven matching ridge characteristics. As the authors of that study acknowledged, “an expert with many years of experience behind him” could make a false identification when comparing two such prints. Unfortunately, no scientific study has been performed that reasonably indicates the probabilities of fingerprints from different people having varying numbers of matching ridge characteristics. See Y. Mark & D. Attias, What Is the Minimum Standard of Characteristics for Fingerprint Identification? 22 Fingerprint Whorld 148, 148. So we are left to ask ourselves, “What is the scientific basis for analysts’ long held position that no to prints are the same?”
B. Fingerprint identification is not used outside of the courtroom setting.
Fingerprint analysis is not used outside of the judicial setting. It is exclusively the providence of the courts. See The Challenge of Fingerprint Comparison Opinions in the Defense of a Criminally Charged Client Mears, Michael and Day, Therese M 19 Ga. St. U. L. Rev. 705. This ;ack of out-of-court use is one of the Daubert factors adopted by the Texas courts which trial courts should look to in deciding whether to admit or exclude expert testimony.
C. There is no uniformity regarding the number of ridge markers required to designate a print as a match.
Latent fingerprint examiners in the United States are currently operating in the absence of any uniform objective standards. The absence of standards is most glaring with respect to the ultimate question that should be asked of all fingerprint comparisons: what constitutes a sufficient basis to make a positive identification? See Simon Cole, What Counts for Identity? The Historical Origins of the Methodology of Latent Fingerprint Identification, 12 Sci. in Context 139, 147 (1999). See also The Challenge of Fingerprint Comparison Opinions in the Defense of a Criminally Charged Client Mears, Michael and Day, Therese M 19 Ga. St. U. L. Rev. 705. As there are no objective industry standards, individual analysts are left to their own, subjective standards in making the determination.
Though the United States has no uniform identification standard, many other countries have set such standards based on a minimum number of points of comparison. Italy retains the minimum standard of seventeen matching points before a comparison can be made, and both France and Australia require twelve points. Thirty is the minimum number required for a “match” in Argentina and Brazil. See David R. Ashbaugh, Quantitative-Qualitative Friction Ridge Analysis: An Introduction to Basic and Advanced Ridgeology 125 (CRC Press 1999) . See also The Challenge of Fingerprint Comparison Opinions in the Defense of a Criminally Charged Client Mears, Michael and Day, Therese M 19 Ga. St. U. L. Rev. 705.
The International Association for Identification (IAI) is a private organization/governing body for forensic science. The IAI makes recommendations to the National Academy of Science which in turn makes recommendations to Congress itself. As far back as 1973 the IAI issued a report that indicated the lack of testing in the fingerprint identification field. The IAI formed a standardization committee for the purpose of determining the minimum number of friction ridge characteristics which must be present in two impression in order to establish a positive identification. After three years of examining the issue the IAI was unable to reach a consensus on the minimum number needed. See The Challenge of Fingerprint Comparison Opinions in the Defense of a Criminally Charged Client Mears, Michael and Day, Therese M 19 Ga. St. U. L. Rev. 705.
Underlying the real reason for not providing a minimum number was “[T]he absence of valid scientific criteria for establishing the minimum number of minutiae has been the main reason that professionals have avoided accepting one.” See David Stoney, The Scientific Basis of Expert Testimony on Fingerprint Identification, Modern Scientific Evidence: the Law and Science of Expert Testimony Section 21-3. The official position of the IAI since 1973 is that no minimum number of corresponding points of identification is required for an identification. Instead, the IAI leaves the determination of a sufficient basis for an identification entirely to the subjective judgment of the particular examiner.
In other words, there is no general acceptance in the scientific community on latent fingerprint analysis requirements. It is purely subjective to the individual examiner.
D. In the United States the results of the fingerprint identification are purely the opinion of the analyst.
David Ashbaugh, a leading forensic scientist stated, that “[i]n some instances we may form an opinion on eight ridge characteristics,” but in other cases, “we may require twelve or more to form the same opinion.” Ashbaugh’s explanation for this sliding scale is that some ridge characteristics are more unique than others. However, fingerprint examiners have never adopted any weighted measures of the different characteristics. Therefore, as Ashbaugh has recognized, the particular examiner’s determination of whether eight or twelve matching characteristics are sufficient in a particular case is entirely subjective. Without objective professional standards, courts are without sufficient basis to judge the validity, admissibility, and worthiness of fingerprint identification testimony. David Ashbaugh, The Key to Fingerprint Identification, 10 Fingerprint Whorld 93 (Apr. 1985). The results are identifications made by examiners using their own ad hoc criteria. Any way you look at it, the positive identification of the Defendant is based solely on the opinion of one person, without any guiding standards.
E. There is no known error rate in fingerprint analysis
There have been no controlled studies to determine the error rate in the field of latent print identification. Without known error rates the State will be unable to meet its burden and the admission of the fingerprint analysis will not meet the Daubert test.
At the very heart of verifiable certainty is a known error rate against which comparisons can be made. In addition to failing to provide a known error rate, the testimony of fingerprint experts also lacks scientific studies upon which predictions of probabilities can be made. Lacking any such probability studies, latent print technicians do not offer opinions of identification in terms of probability. Indeed, the rules of their primary professional association, the IAI, actually prohibit latent print examiners from doing so. Instead of testifying regarding probabilities, latent print examiners make the claim of “absolute certainty” for their identifications. Examiners provide an opinion to the fact finder that the latent print at issue was made by a particular finger to the exclusion of all others in the world! Not even DNA experts make such bold statements. Such assertions of absolute certainty are inherently unscientific. See The Challenge of Fingerprint Comparison Opinions in the Defense of a Criminally Charged Client Mears, Michael and Day, Therese M 19 Ga. St. U. L. Rev. 705. See also Robert Epstein, Fingerprints Meet Daubert: The Myth of Fingerprint “Science” is Revealed, 75 S. Cal. L. Rev. 605, (March 2002).
F. A complete lack of studies exists regarding the reliability of latent fingerprint examinations or any type of peer review.
In addition to the lack of basic reliability studies, no testing has been conducted to determine the probability of two different people having a number of fingerprint ridge characteristics in common. And to the contrary, the studies and testimony of experts have shown people can have numerous ridge characteristics in common. See paragraph A above.
This is in sharp contrast to the relatively new field of DNA analysis, where scientific testing has been done to calculate the probability of a
coincidental match. See Robert Epstein, Fingerprints Meet Daubert: The Myth of Fingerprint “Science” is Revealed, 75 S. Cal. L. Rev.
605, (March 2002). David Stoney, a leading forensic science scholar, and a trained fingerprint analyst, has written:
[T]here is no justification [for fingerprint identifications] based on conventional science: no theoretical model, statistics or an empirical validation process. Efforts to assess the individuality of DNA blood typing make an excellent contrast. There has been intense debate over which statistical models are to be applied, and how one should quantify increasingly rare events. To many, the absence of adequate statistical modeling, or the controversy regarding calculations, brings the admissibility of the evidence into question. Woe to fingerprint practice were such criteria applied! Much of the discussion of fingerprint practices in this and preceding sections may lead the critical reader to the question “Is there any scientific basis for an absolute identification?” It is important to realize that an absolute identification is an opinion, rather than a conclusion based on scientific research. The functionally equivalent scientific conclusion (as seen in some DNA evidence) would be based on calculations showing that the probability of two different patterns being indistinguishably alike is so small that it asymptotes with zero . . . . The scientific conclusion, however, must be based on tested probability models. These simply do not exist for fingerprint pattern comparisons”. See David Stoney, Measurements of Fingerprint Individuality, Advances in Fingerprint Technology at 331.
The United States Department of Justice concurred in Mr. Stoney’s assessment when it began soliciting validation studies regarding fingerprint identification 2000. As the Department of Justice stated in its solicitation, “the theoretical basis for [fingerprint] individuality has had limited study and needs additional work to demonstrate the statistical basis for identifications.” See Solicitation, Nat’l Inst. Of Justice Forensic Friction Ridge (Fingerprint) Examination Validation Studies (March 2000). See also Robert Epstein, Fingerprints Meet Daubert: The Myth of Fingerprint “Science” is Revealed, 75 S. Cal. L. Rev. 605, (March 2002).
G. Positive identification of fingerprints have led wrongful convictions
Dr. Simon Cole, an assistant professor of criminology at the University of California-Irvine authored an article entitled More than Zero: Accounting for Error in Latent Fingerprint Identification which was published in the Journal of Criminal Law & Criminology with Northwestern University School of Law. Dr. Cole’s article details eighteen of the most famous instances of false positive identifications of fingerprints. In each of these cases, people were arrested and most spent considerable time in jail. This includes a recent case in 2004 when the FBI arrested an attorney in Oregon as a material witness in the Spain train bombings of that same year. After the FBI finger analysis stated that it was a 100% match, the lawyer, Mr. Mayfield was arrested and held for two weeks. It was ultimately learned that this 100% positive match was completely wrong. Mr. Mayfield was released with an official apology from the FBI.
