Evidential power and explanatory gap in forensic imaging

Technological innovations are rapidly driving the development of forensic medicine. Imaging techniques are used not only to diagnose but also to provide causal interpretations for a chain of events in criminal investigations. This paper argues the necessity of upgrading the forensic toolkit with modern digital imaging technology. The possibilities and limitations of identifying evidential content in images are elucidated using the example of the special role of color and the special methods with which new imaging techniques in the discipline are evaluated are discussed. The aspect of reliability is exemplified by the results from two experiments that tested interrater agreement in the assessment of classification stages from radiographs. The results of these two experiments illustrate that an element of uncertainty remains between information contained in imaging data and individual diagnostic interpretation of these data depending on experience that can be influenced by other factors. Various underlying reasons are discussed along with the various types of errors that can occur using imaging techniques. In forensic examinations visual findings cannot be evaluated, interpreted, or integrated simply by transferring skills and proficiencies from other disciplines. The techniques applied need to be constantly adapted and developed. Specifically, this means that acquiring modern image generating equipment is not enough and practitioners also must learn how to use the technology to evaluate the visual data generated from a forensic aspect.