When Verification Says Inconclusive
Examiner A, a 12-year examiner, concludes that a latent palm print from a windowsill identifies a suspect. The latent is from the thenar area, has 17 minutiæ, and lacks a clear delta. Examiner B performs a blind verification and returns 'inconclusive,' citing two concerns: a short ridge in the latent that has no counterpart in the palm exemplar, and a gap in the exemplar where the latent shows continuous ridges. Unit policy requires a second examiner's agreement before an identification is reported. The trial is in three weeks. The prosecutor calls the supervisor and asks whether the identification 'stands'; the supervisor proposes that A and B 'talk it out' and, if B still disagrees, that A's conclusion be reported because A has more experience and the latent is the only evidence placing the suspect at the scene.
1. Evaluate the supervisor's proposal against verification policy and good practice.
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The proposal is wrong on two counts. Verification is an independent technical check, not a negotiation, and experience is not evidence. If policy requires agreement, the identification is not reportable as an identification while verification is inconclusive.
'Talking it out' may be appropriate only after B has documented an independent conclusion, and A's conclusion must not be disclosed before B's documentation, or the verification is no longer blind. The supervisor should not pressure B or treat seniority as a tiebreaker. The options are an independent blind examination by a third qualified examiner, a formal conflict-resolution procedure, or reporting the result as inconclusive.
2. How should the two differences be investigated technically?
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For the short ridge, determine whether it is a true ridge or an artifact such as debris, a crease, a scar, or the edge of the impression. Examine the original lift and photographs, not only the enhanced image. For the gap in the exemplar, determine whether it is an inking defect, a scar, a crease, or a genuine absence, and obtain a new palm exemplar and any prior exemplars.
For a thenar latent, confirm that the area is the same and check the flexion creases and wrist crease. Use level 3 detail around both sites. If the short ridge is a crease artifact and the gap is an inking defect, both are explained. If either remains a reliable, unexplained difference, that weighs toward inconclusive or exclusion.
3. What should be reported if the disagreement cannot be resolved, and how should that be explained to the prosecutor?
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Report 'inconclusive/no identification' rather than identification. Explain that the examiner's opinion and the verification status are separate: an unverified identification cannot be presented as an identification, and the evidence should not be described as a match.
The prosecutor can seek an independent examination by another agency. Document the disagreement, the blind conditions, and the resolution attempts. Also review whether the pressure of the case, with this being the only evidence placing the suspect at the scene, influenced the original analysis.