Government-sponsored Report on Latent Fingerprint Work in Criminal Investigation and Prosecution

From NIST's Office of Law Enforcement Standards (OLES), as posted on February 17, 2012: “Expert Working Group Reduces Human Error Analyzing Fingerprints.” Sounds great. So how has the group succeeded in reducing these errors? Alas, clicking on the link reveals that, as yet, the group has not prevented a single error, human or inhuman. But NIST has released a long overdue report prepared by an expert working group that it assembled and funded for an extended period.

The final 234-page report from the committee of 34 experts contains 34 recommendations to improve latent print examination in criminal investigations and in presentations of the findings to police, lawyers, judges, and juries. The committee believes that implementation of these recommendations eventually could reduce the incidence of errors in latent print work and in the understanding of the results. The recommendations are a kind of wish list with entries that range from studying how to test the vision of fingerprint analysts; to educating examiners “in the scientific method” and in probabilistic and statistical thinking; to creating “a culture” in which examiners can confess honest error without fear of punishment; to monitoring the day-to-day work and courtroom testimony; and to certification for all analysts and accreditation for all laboratories.

Lawyers will be interested in the admonishments in the report about insulating examiners from unnecessary extraneous information; contemporaneously documenting the thought processes of examiners; making complete reports available; and curbing exaggerated claims of conclusive identifications. Concluding that existing data does not permit reasonably accurate estimates of error rates in real-life fingerprint identifications, for example, the report insists that an “expert should not state that errors are inherently impossible or that a method inherently has a zero error rate.” Likewise, the report states that “latent print examiners should not report or testify, directly or by implication, to a source attribution to the exclusion of all others in the world.” However, the group of latent print examiners, forensic laboratory scientists and managers, psychologists, engineers, statisticians, and lawyers, was unable to agree on what statements should replace such well entrenched testimony.

Given these tensions and ambitions, will NIST's premature assertion that “Expert Working Group Reduces Human Error Analyzing Fingerprints” come true? One can only hope for the best.

--DH Kaye, Feb. 18, 2012

Irony: The NIST statement accompanying this report on error and human factors has errors of its own. The actual publication date was February 17, not February 9. Authors’ names are not always spelled correctly, and support staff are listed as authors. No doubt, this says something about human fallibility if not human factors.

Disclosure: The author of this note was a working group member and the editor of the report described here. See Expert Working Group on Human Factors in Latent Print Analysis, Latent Print Examination and Human Factors: Improving the Practice through a Systems Approach, Feb. 2012.