1 - ‘Seeing for Real’: Forensic Pathologists Testing the Demonstrative Power of Postmortem Imaging

Summary

In cases of homicides or suspicious deaths, corpses undergo a series of technical and scientific tests during examination to make them ‘talk’ and to establish the cause of death. Nowadays, modern postmortem imaging is increasingly being used to complement conventional autopsy (Grabherr et al, 2017). Specific features characterize each imaging technique. For example, postmortem computed tomography (PMCT) provides a view of the whole body in just a few minutes and allows excellent visualization of the skeleton (trauma cases), gases, fluids and foreign materials (such as projectiles) (Grabherr et al, 2017). PMCT angiography artificially reestablishes blood circulation by means of a perfusion system, enabling the full investigation of the vascular system; most importantly, it can detect the exact source of bleeding, for example, in a case of aneurysm or haemorrhage (Grabherr et al, 2018). Postmortem magnetic resonance imaging (MRI) is the only radiological technique that provides good visualization of soft tissues and organs; however, its use is still limited to paediatric cases due to the duration of the examinations and the lack of scientific research supporting its diagnostic power in postmortem cases (Magnin et al, 2020). Postmortem imaging is a unique visualization tool that allows visual examination of the inside of a body before opening it. Thus, forensic pathologists would know in advance the lesions they will find during the autopsy, enabling them to efficiently prepare their instruments and conduct an accurate examination. These techniques also make it possible to observe lesions that are difficult to detect through autopsy, such as multiple fractures in the case of polytrauma or even the source of haemorrhage. In this way, autopsy and imaging are considered complementary techniques in the scientific literature, which argues that their combined use improves the sensitivity and quality of postmortem examinations (Grabherr et al, 2018; Michaud et al, 2019).

However, the challenge of integrating postmortem imaging techniques into the forensic investigation process cannot be limited to simply adding further techniques to the chain of investigations on a body. During our ethnographical fieldwork in a forensic medicine department that uses and develops postmortem imaging, we were confronted on several occasions with debates between forensic doctors and imaging specialists discussing discrepancies between radiological interpretations and direct observations of the body.