Another "View" of Fingerprint Evidence

Article excerpt

Clearer exhibits better enable judges and jurors to evaluate the comparability of latent and known fingerprints.

In the vast majority of cases in which the prosecution presents fingerprint testimony, the jury convicts. That result is not surprising. Most members of the general public firmly believe fingerprint examiners' claim that they can accurately match crime scene impressions with the known fingerprints of defendants. Most prosecutors share that belief, and fhey consequendy frequently offer examiners' testimony about fingerprint analysis. Similarly, the clear majority of judges subscribe to the belief; and given that belief, in the typical case they admit fingerprint testimony over a defense objection. And since juries draw their ranks from the members of the general public, jurors tend to accept such testimony and confidentiy rely on it as a basis for convictions. This widespread belief helps explain why die defense probably loses over 90 percent of the trials at which the prosecution presents an examiner's testimony to a fingerprint match.

Yet, for well over a decade there have been concerted defense attacks on the reliability of fingerprint examination testimony.1 In 2009, the National Research Council of the National Academy of Sciences released its report entitled Strengthening Forensic Science in the United States: The Path Forward. The report added fuel to the defense attacks. The report states that in the popular AGE-V (Analysis Comparison Evaluation Verification) method of analysis, "examiners must make subjective assessments throughout."2 Furthermore, the report took sharp issue with the assertion of some examiners that fingerprint analysis has "a zero error rate."8

The recent experience of some image analysts appears to confirm the National Research Council's conclusion that the accuracy of fingerprint analysis has been overstated. These analysts have developed a number of techniques for assessing the accuracy of fingerprint analysis. One such technique involves the use of a simple computer methodology. More specifically, they attempted to improve the displays by placing a clear image of the crime scene latent on top of the image of the known fingerprint. This method differs from the old fashioned sideby-side display. This new method better enables the judge and jury to visualize the comparison and to see for themselves whether the prosecution expert is correct in opining that there is a match.

In several cases, working together with defense counsel, these experts have critically evaluated examiners' opinions that a crime scene image matched the image of a known fingerprint of a particular defendant. To be sure, these cases represent a small sample. However, in most of them, even though the examiner had declared a match, the image experts' exhibits strongly suggested that at most the examiner ought to have testified that the result of the comparison was inconclusive. In one Case, although again the expert had testified to a match, the exhibit seemingly dictated the conclusion that there were so many evident points of dissimilarity that there was no match. In all but one of these cases, after the image experts shared their exhibits with the government, the government decided against proceeding to trial. Charges Were dismissed, or the prosecution offered the defendant a much more favorable plea bargain after viewing the new exhibits.

The exhibits shown here were prepared in some Of these cases.4 In case 1, the use of the exhibits contributed to a hung jury; hi the other cases after the presentation of the exhibits to the government the prosecutor offered a more attractive plea bargain. The first three exhibits relate to case 1. The exhibits are: the prosecution exhibit, a conventional defense side-by-side exhibit, and the new on-top exhibit prepared by the imaging experts.

Global attacks

In the past, many defense counsel have made "global" attacks on the validity of fingerprint analysis. …