DEEN
Dipl.-Biol. Bastian J. Hirthammer
Forensic Anthropology

Professional framework

Professional standards and the expert role

Expert work here follows methodological and professional principles: independence, transparency, clear role boundaries, and an open statement of the limits of the material.

These are not merely formal requirements, but standards for the concrete work in the individual case. They include the separation between the factual basis, expert assessment, and legal evaluation, the disclosure of foundational facts, and a restrained handling of methodological limits.

How these principles work out in practice is shown in more detail on the pages dealing with forensic image comparison and procedure and initial enquiry. What matters here is methodological discipline, transparent reasoning, and a clear statement of the limits of any conclusion.

Role Independent · impartial · bound to the evidential question
Method Feature analysis · comparability · open statement of limits
Transparency Qualification · working method · documentation

Professional standards and the expert role · Role profile

Role of the expert witness

The forensic expert is not a party to the proceedings and not an aide to a preferred result. He works independently, impartially, and with reference to the specific evidential question. His task is to explain to the court or instructing body, in a traceable way, what the material supports and what it does not. The expert role concerns the professional assessment of the material and the scope of any conclusion; legal evaluation and decision remain with the court or commissioning authority.

This also includes openly identifying methodological limits. Where image material is not sustainable, comparison images are unsuitable, or additional records are missing, this is not a side issue, but part of a proper expert assessment.

Professional standards and the expert role · Professional benchmark

Professional standards

Morphological identity opinions require specific expertise, practical experience, and methodological care. The work does not consist in mere recognition or an overall visual impression. It requires a structured analysis of individual morphological features, an examination of their comparability within the material of the case, and a traceable classification of similarities, differences, and uncertainties.

The professional basis therefore includes a separation between image-suitability review and the substantive assessment itself, careful documentation of the working material, disclosure of relevant prior selections, and restraint toward a degree of precision that the material does not in fact support.

A methodologically sound expert report also depends on clearly separating robust conclusions from methodological limits.

Professional standards and the expert role · Core principles

Independence and transparency

Information on qualifications, judicial practice, memberships, and publications identifies the professional basis of the expert work. Equally important is transparency in the individual case: which files were available, which processing steps served only visualisation, and which features were in fact comparable.

This transparency protects not only the traceability of the opinion, but also the proper distinction between technical preparation, professional finding, and the later judicial evaluation of evidence. It also requires a clear distinction between what rests on the expert’s own findings and what has merely been taken over from file material, prior information, or statements by others.

Professional standards and the expert role · Methodological integrity

Limits and disclosure

Not all material permits a sufficiently supported conclusion. Blur, perspective, covering, technical artefacts, or missing comparison images may substantially limit the evidential value. In such cases, disclosure matters more than rhetorical sharpness. A methodologically careful opinion therefore also states when only a preliminary review is sensible or when particular lines of conclusion are not methodologically supported.

The same applies to prior nominations, hit lists, or other preselection steps. Such information may be relevant in the proceedings, but it must not covertly steer the professional feature analysis.

The assessment requires a documented basis; this includes in particular the assignment, the image material, the basis of comparison, and the sources used in the specific case. Without such a documented basis, the later expert assessment loses traceability and professional verifiability. Where staff members or third parties are involved in a way that is significant for the opinion, this too must be made transparent.

Professional standards and the expert role · Quality assurance

Quality assurance and continuing education

Professional standards remain reliable only if they are tested in practice, updated, and accompanied by continuing education and transparent quality assurance. That includes keeping track of methodological developments, engaging critically with current publications, and regularly sharpening one’s own standard of judgement.

In forensic age estimation, this is further reflected in the documented annual participation in the AGFAD proficiency test since 2009. Such evidence does not replace the assessment of an individual case, but it does show a willingness to have methodological quality regularly tested rather than merely invoked.