Performance criticality as a structural property of forensic expertise: Evidence from an institutional certification system.

Forensic expert certification relies on evaluation systems designed to assess professional performance under high technical, analytical, and probative demands. However, certification outcomes are often interpreted through aggregate indicators, such as approval rates or overall mean scores, which may obscure where performance is stable, sensitive, or insufficient within the internal structure of expert work. This study proposes a Performance Criticality Index to examine certification evidence at the level of competency units in a national institutional forensic certification system in Colombia. The index combines two dimensions that are central to certification decisions: the distance between observed performance and a predefined sufficiency threshold, and the variability of performance across evaluation cycles. Using aggregated historical results from forensic certification processes conducted between 2021 and 2025, the analysis identifies differentiated configurations of performance rather than global levels of achievement. The findings show that criticality is not uniformly distributed across disciplines or competency units. Robust competencies coexist with localized sensitivity, distributed sensitivity, concentrated criticality, and structural insufficiency. Criticality tends to emerge in units involving integrative forensic reasoning, analytical reconstruction, or the formulation of expert conclusions, whereas highly standardized technical-procedural components tend to show greater stability. The index does not measure expertise directly; rather, it identifies competency units in which certified performance may be structurally vulnerable because mean scores approach the sufficiency threshold while dispersion remains high. The proposed approach contributes to interpreting certification evidence beyond averages and to understanding how evidence, technique, and expert judgment are articulated in forensic practice.