PCAST Report (2016)

The PCAST Report was a report generated by the President’s Council of Advisors on Science and Technology. The report assessed seven of the most often used feature comparison methods in the criminal justice system including fingerprint comparison.  It is important to note the report’s definitions of the terms “foundational validity” and “validity as applied,” which the authors used to frame their assessment of the disciplines and which they equated to the requirements of Federal Rule of Evidence 702:

“For complete clarity about our intent, we have adopted specific terms to refer to the scientific standards for two key types of scientific validity, which we mean to correspond, as scientific standards, to the legal standards in Rule 702 (c,d):

(1) by “foundational validity,” we mean the scientific standard corresponding to the legal standard of evidence being based on “reliable principles and methods,” and

(2) by “validity as applied,” we mean the scientific standard corresponding to the legal standard of an expert having “reliably applied the principles and methods”

As it related to fingerprint comparison the PCAST Report found:

“PCAST found that latent fingerprint analysis is a foundationally valid subjective methodology but noted substantial false positive rates. PCAST also expressed concern that these false positive rates would be underappreciated by jurors, who PCAST believes have grown accustomed to the perceived infallibility of the discipline.

The report calls for analysts to disclose false positive rates based on properly designed validation studies in reporting the results of their latent fingerprint examinations. While determining the discipline to be foundationally valid, PCAST nevertheless observed several issues concerning validity as applied, including: confirmation bias (noting that FBI examiners were found to have modified their initial observations to comport to the characteristics of an apparently matching exemplar); contextual bias (noting that examiners’ conclusions could be affected by information about the facts of the case); and the need for more rigorous proficiency testing.”