Nine Minutiae, One Disputed: Resolving a Verification Conflict
L-1 is a black-powder lift from the chrome grab bar of a shower enclosure in an assault case. The lift measures 14 by 22 mm and shows a partial right loop with nine features that Examiner R considers clear. R individualizes to the suspect and writes the report. During verification, Examiner T agrees on eight features but calls the ninth - a bifurcation 1.5 mm from the lower edge of the lift - a wrinkle artifact from the hinge lifter, and would conclude inconclusive. Both are CLPEs in the same unit, and the laboratory SOP requires agreement of two certified examiners before an identification is reported. Trial is in nine days. The shower bar was released to the homeowner after the lift was taken, so the substrate cannot be re-examined. No note was made at the scene about the hand position on the bar. The original lift, the hinge card, and two overall scene photographs with a scale - slightly out of focus - are available.
1. What must happen before any report is issued in this case, and who decides?
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The disagreement is a technical conflict between two trained examiners, so the laboratory's conflict-resolution procedure governs - not seniority, not the trial date, and not a vote. Both examiners should re-examine the original lift independently at low power and under oblique lighting, with enlargements on the bench, and each should point to the disputed ridge event in the same location. Disagreements that look like 'different features' are often really disagreements about where a ridge ends or whether a ridge edge is continuous.
The narrow question is whether the bifurcation is anatomical or an artifact. Both examiners should then answer a second question separately: if the ninth feature is set aside, do the remaining eight, in the low-distortion zone, meet the laboratory's documented threshold for individualization? If yes, the identification can rest on those eight with the disputed feature excluded from the stated basis. If no, the conclusion must fall to inconclusive - a conclusion cannot be carried by a feature that has not survived verification, and it cannot be 'identification by majority.'
If R and T still disagree, a third CLPE who has not seen the case should examine it blind. Every opinion, its date, and the technical rationale for the final conclusion go in the file. The nine-day trial date has no bearing on the conclusion; it affects only how quickly the laboratory communicates the result.
2. How should the distortion at the edge of the lift be assessed and documented, and how does that assessment bear on the disputed feature?
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Document distortion rather than asserting it. Useful steps: (1) build a distortion map or annotated overlay marking ridge flow direction, areas of compression or stretching, and the position of the disputed bifurcation within 1.5 mm of the lift edge; (2) measure ridge-to-ridge spacing at the centre of the impression and near the edge, and state the percentage change; (3) map the impression onto the geometry of the grab bar, since a flat tape pressed onto a cylinder compresses one side and stretches the other, and distortion increases toward the edge; (4) compare the lift to the hinge card to see whether the hinge fold falls where the disputed feature sits; (5) use the scene photographs, even out of focus, to estimate hand position and the direction of contact.
Two different phenomena must be separated. Genuine geometric distortion bends and stretches ridge spacing but leaves ridge edges continuous and pore positions internally consistent; it does not create a branch. A crease or wrinkle in the lift itself produces a linear discontinuity that crosses ridge flow without regard to anatomy, often with a light or dark line running through it, and it can mimic a bifurcation. Under the stereo microscope a real bifurcation shows continuous ridge edges and a normal ridge width on both branches; a wrinkle-created 'branch' does not.
The documentation should state explicitly whether the feature was confirmed as anatomical, rejected as an artifact, or left unresolved - and the conclusion must match that finding. Saying 'distortion is present' is not a substitute for showing where and how much.
3. If the identification stands after conflict resolution, what belongs in the report and what must be disclosed at trial?
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The report should state the conclusion, the basis for it in concrete terms (number of features relied on, area and clarity of the impression, the region of the impression used), and any limitation the examiner accepted, such as exclusion of an edge feature from the basis. It should not characterize the verification as unanimous if it was not.
The bench notes are the record of the process and must remain intact - the initial dissent, both examiners' dates, and the rationale for resolution all stay in the file and are discoverable. Nothing is rewritten, removed, or summarized away. The fact that the shower bar was released and could not be re-examined belongs in the notes as well.
At trial the examiner should testify truthfully about how the identification was verified: that a second certified examiner initially assessed the impression as inconclusive, what the specific concern was, and how it was resolved - by re-examination, by a third opinion, or by the conclusion resting on the remaining features. Testimony should not imply that the verifier simply erred, and should not present the process as frictionless. If the disputed feature was excluded from the basis, say so; that is a strength, not a weakness, because it shows the conclusion survived the challenge. If the final consensus was inconclusive, the report says inconclusive and the examiner does not testify to an identification with a hedge attached.