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Monday, May 10, 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

Spanish Police Doubt Fingerprint ASSOCIATED PRESS - May 9, 2004 ...Spanish investigators have serious doubts as to whether the fingerprint found on a plastic bag tied to March 11th Spain explosions is that of Oregon lawyer...

Live-Scan Challenged in Lawsuit   EMEDIAWIRE  - May 7, 2004 ...a defect in Livescan poses the potential for false convictions that has already put innocent people in jail...

Misfits Dumped into Key Cop Unit BOSTON HERALD, MA  - May 6, 2004 ...the Boston Police ID Unit has been a "dumping ground'' for troubled cops, according to police sources and department records...

Nichols Trial: Judge Allows Fingerprint Testing CHANNEL OKLAHOMA, OK  - May 6, 2004 ...defense council say unidentified fingerprints could point to more suspects…


Last week, Craig Coppock brought us a new and original paper on recognition and induction in forensic science.  Last week, the Byron Mitchell case made the news again!  This week, Andre Moenssens examines the 3rd Circuit US Court of Appeals' decision upholding the conviction of Byron Mitchell.


“Fingerprinting” Satisfies Daubert, U.S. Court of Appeals for the 3rd Circuit  Affirms!
by Andre A. Moenssens

The Mitchell case is old news to latent print examiners. Briefly, Pennsylvania U.S. District Court Judge Joyner conducted a five-day Daubert hearing in United States v. Byron Mitchell in 1999, at the conclusion of which the judge ruled that “fingerprinting” satisfied all Daubert factors. He also took judicial notice that “human friction ridges are unique and permanent throughout the area of the friction ridge skin, including small friction ridge areas, . . .”  With the pre-trial evidentiary issues settled, Mitchell was thereafter tried and convicted in 2000. Not surprisingly, he appealed. On April 29, 2004, the United States Court of Appeals for the Third Circuit, in an opinion written by Circuit Judge Becker, upheld the conviction as well as Judge Joyner’s conclusion that “fingerprinting” evidence was admissible. The reviewing court, however, did hold, however, that Judge Joyner improperly took judicial notice of the uniqueness and permanency aspects of fingerprints. We will discuss the reasons herein. Since the official citation is not available, the case may be referred to as: United States v. Mitchell, … F.3rd ….., 2004 WL 908359 (3rd Cir. [Pa.], 2004). The entire Third Circuit Court opinion can be found on the CLPEX Mitchell page.

It serves no useful purpose to reiterate the entire background of evidence presented at Mitchell’s Daubert hearing. We will assume our readers are familiar with not only Daubert’ reliability factors, but also with the Mitchell evidence, as well as the intervening decision in the case of United States v. Llera Plaza, to which the Mitchell appeals court opinion makes reference.  At this point, it is useful to review a few significant points of Mitchell’s appellate decision.

The Third Circuit Court of Appeals Decision in Mitchell

The Court of Appeals ignored an issue that had been hotly debated at the Daubert hearing -- the issue whether fingerprint identification was a “science.”  The United States Supreme Court decision in Kumho Tire v. Carmichael, 526 U.S. 137 (1999), made it unnecessary to draw a distinction between scientific and non-scientific expert testimony, inasmuch as Kumho Tire had made it clear that the “gatekeeper” role of the trial judge, who is charged with keeping out of court “unreliable” opinion evidence, applied to all expert opinions, whether deemed scientific, technical, or experience-based.  The appeals court explored each one of the Daubert factors in its opinion.  In doing so, the court’s decision, while ultimately favorable to the prosecution, was not overwhelmingly laudatory.

The first factor -- Testability: Testability refers to “whether the premises on which fingerprint identification relies are testable – or, better yet, actually tested.”  The court concluded that the premises that friction ridge arrangements are unique and permanent, and that a positive identification can be made from fingerprints containing sufficient quantity and quality of detail, were testable and had been tested in several ways. In that regard, the court referred to the FBI’s AFIS computer comparison of 50,000 left-sloped whorl patterns against a database of another 50,000 sets of 10-prints, thus involving 2.5 billion comparisons. The experiment showed there were no true matches of prints coming from different digits. The court referred to several other tests, such as those involving the prints of identical twins, and the fact that an FBI survey showed no state identification bureaus had ever encountered two different persons with the same fingerprint.

The second part of the “testability” factor involved the fact that making a positive identification depends on “fingerprints containing sufficient quantity and quality of detail.”  The court was a little troubled that the standard of having a point-system had been abandoned and that the FBI relied on an “unspecified, subjective, sliding-scale mix of ‘quantity and quality of detail’,” but since FBI expert Steven Meagher had identified 14 points of Level 2 detail in his identification of Mitchell’s right thumbprint to the crime scene latent, the court saw the issue in this case as being whether having fourteen points of Level 2 detail was enough for a positive identification. Referring again to the AFIS computer check with simulated latents (exhibiting only 1/5th of the size of a rolled fingerprint) and the survey which showed no identification bureau had ever found two matching prints on different digits, the court there found “perhaps the strongest support for the government on this point.” It concluded that the “hypotheses that undergird the discipline of fingerprint identification are testable, if only to a lesser extent actually tested by experience.”

The Peer Review factor
:  The court did not seem overly impressed by the fact the testimony on this factor had largely centered on whether the “verification” step of ACE-V constitutes effective peer review.  Dr. Simon Cole, testifying for the defense, had suggested that fingerprint examiners have developed an “occupational norm of unanimity” which discourages dissent. While acknowledging that the “cultural mystique” attached to fingerprinting may infect the peer review process, the court nevertheless concluded that when looking at the entire picture, “the ACE-V verification step may not be peer review in its best form, but on balance, the peer review factor does favor admission” of friction ridge comparisons and individualizations.

The Error Rate
: This is where the experts on both sides had waged the greatest battle at the Daubert hearing. The appeals court took the courageous step in distinguishing between two error rates: false positives and false negatives. The defense had made a lot of testing errors where examiners had failed to make identifications that could and should have been made. In that regard, the court recognized that a high false negative rate may not be desirable as a matter of law enforcement policy, but said that “in the courtroom, the rate of false negatives is immaterial to the Daubert admissibility of latent fingerprint identification offered to prove positive identification because it is not probative of the reliability of the testimony for the purpose for which it is offered (i.e., for its ability to effect a positive identification.” [Italics in the court’s opinion.]

False positives, on the other hand, would be most troublesome. But the court concluded that, “where what is sought to be proved is essentially a negative (i.e., the absence of false positives) it seems quite appropriate to us to use a burden-shifting framework.” Where the government experts testify to being unaware of significant false positive identifications, the burden of producing contrary evidence may reasonably be shifted to the defense. While the error rate may not have been precisely quantified, the court was persuaded that the methods of estimating it show it to be very low.

The Maintenance of Standards
:  Again, the court found this standard to be “lacking in some measure.” The procedural standards of ACE-V were deemed to be “insubstantial in comparison to the elaborate and exhaustively refined standards found in many scientific and technical disciplines” and the court found that this factor did “not favor admitting the [fingerprint] evidence.”

The General Acceptance factor
:  Little needs to be said on this factor, which the court found to be clearly weighing in favor of admitting the evidence.

To conclude, the appeals court’s decision was that, on the record presented to it, an analysis of the Daubert factors shows that “most factors support (or at least do not disfavor) admitting the government’s” evidence on friction ridge individualizations. Thus, it held that the District Court did not abuse its discretion in admitting it. This is by no means a strong endorsement, even though it may be seen as such in the practical effect the opinion will likely have.

Several specific points in the Third Circuit Court opinion emphasize the court’s recommendations for future practice:

1.  Examiner error rates:  Perhaps the reviewing court’s most relevant observation was that the degree of confidence the system has in friction ridge individualizations depends very heavily on the competence of the examiner, who did the analysis and testifies in court.  The court suggested that “prosecutors would be well-advised to elicit the testimony about their experts’ personal proficiency” as exhibited in proficiency testing inside and outside of their agencies. No such testimony had been presented with respect to the government’s experts at the trial: Steven Meagher and Wilbur Johnson. While neither had testified about their own error rate as practitioners, that “putative blemish on their qualifications” was overcome by “Agent Meagher’s uniquely strong qualifications” and the confirmatory identifications from state agencies.  The prosecutor did in fact inquire as to Mr. Johnson’s FBI proficiency examinations, but the defense objection to the question had been sustained. The appeals court suggested that Judge Joyner had been wrong to sustain the objection.

2.   No Limitation on Defense Expert Testimony
: The reviewing court also suggested that there should be no limitation on the testimony defense experts seek to offer. In that regard, the court noted:  “Experts with diametrically opposed opinions may nonetheless both have good grounds for their views, and a district court may not make winners and losers through its choice of which side’s experts to admit when all experts are qualified  [Our emphasis].”  But the court went further and said that if there was any question about an individual’s competence on a given issue, the court should err on the side of “admitting any evidence having some potential for assisting the trier of fact.”  A lot of space was devoted in the latter part of the court’s opinion to a discussion of the limitations believed to have been imposed on the testimony of some defense experts. No limitations should be imposed, the court said. What saved the case from a reversal on that point was perhaps the failure of the defense to effectively preserve its objections.

3.   Will there be more or fewer Daubert hearings in the future?
  On this issue, the court’s opinion was somewhat obscure. First, it said that its Mitchell decision did NOT announce “a categorical rule that latent fingerprint identification evidence is admissible in this Circuit.” But then it also said that nothing in the opinion “should be read to require extensive Daubert hearings in every case involving latent fingerprint evidence.” Further either muddling or clarifying what went before, the opinion then stated that “a district court would not abuse its discretion by limiting, in a proper case, the scope of a Daubert hearing to novel challenges to the admissibility of latent fingerprint identification evidence – or even dispensing with the hearing altogether if no novel challenge was raised.”  What this probably means is that Third Circuit district courts will now refuse to conduct Daubert hearings unless the defense raises arguments not considered in the Mitchell litigation.

4. No “judicial notice” for fingerprinting.
  Judge Joyner had taken judicial notice that “human friction ridges are unique . . . including small friction ridge areas. .  .  .” What does “taking judicial notice” really mean? Instead of requiring the parties to present proof of a given fact, a court is permitted to take “judicial notice” of that fact without requiring proof thereof if the fact is “not subject to reasonable dispute.” While there have been state reviewing court decisions going back 40 or more years taking judicial notice of the uniqueness of fingerprints, the court found these decisions not only not binding on the court, but clearly distinguishable, since the decisions dealt with the uniqueness of complete fingerprints. That was not the issue here; the issue was uniqueness of small areas of friction skin as visualized through a latent impression. As to that issue, the appeals court felt that the very fact it took five days of testimony to establish the “uniqueness” of “small areas of friction skin” showed that the fact was by no means “generally known” or “capable of ready determination.”  Therefore, Judge Joyner’s “judicial notice” ruling was in error. Because it was not deemed to likely have altered the outcome of the case,  it was considered to be “harmless error” not requiring a reversal.

The Michell case has precedential (binding) value for the Third Circuit. That means the district courts in the Third Circuit must follow it. As to all other courts, the decision is merely persuasive precedent, although it is likely to be widely quoted and followed in other federal as well as in state jurisdictions.


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