Tomáš Vojtíšek

Using drone-mounted cameras for on-site body documentation: 3D mapping and active survey

Recent advances in unmanned aerial technology have substantially lowered the cost associated with aerial imagery. As a result, forensic practitioners are today presented with easy low-cost access to aerial photographs at remote locations. The present paper aims to explore boundaries in which the low-end drone technology can operate as professional crime scene equipment, and to test the prospects of aerial 3D modeling in the forensic context. The study was based on recent forensic cases of falls from height admitted for postmortem examinations. Three mock outdoor forensic scenes featuring a dummy, skeletal remains and artificial blood were constructed at an abandoned quarry and subsequently documented using a commercial DJI Phantom 2 drone equipped with a GoPro HERO 4 digital camera. In two of the experiments, the purpose was to conduct aerial and ground-view photography and to process the acquired images with a photogrammetry protocol (using Agisoft PhotoScan® 1.2.6) in order to generate 3D textured models. The third experiment tested the employment of drone-based video recordings in mapping scattered body parts. The results show that drone-based aerial photography is capable of producing high-quality images, which are appropriate for building accurate large-scale 3D models of a forensic scene. If, however, high-resolution top-down three-dimensional scene documentation featuring details on a corpse or other physical evidence is required, we recommend building a multi-resolution model by processing aerial and ground-view imagery separately. The video survey showed that using an overview recording for seeking out scattered body parts was efficient. In contrast, the less easy-to-spot evidence, such as bloodstains, was detected only after having been marked properly with crime scene equipment.

Applying 3D prints to reconstructing postmortem craniofacial features damaged by devastating head injuries

Postmortem facial identification is one of the most common techniques for establishing a deceased persons identity. In victims suffering from devastating cranial injuries, the feasibility of facial identification tasks can be compromised by damage to or disfigurement of the identifying cranial features. Although there are several reconstructive approaches, which help experts to restore the essence of persons physical appearance, thus enhancing the chances of recognition, only a few of them involve restoring the fractured cranial bones as the foundation for the reconstructed soft tissues. Here, we propose a technique based on replacement of heavily damaged hard tissues with generic prosthetics manufactured by 3D printing. Our approach does not require medical imaging technologies or other costly lab equipment. It is simple, affordable and relatively labor-efficient. The deceaseds reconstructed craniofacial features can be subsequently assessed, photographed, drawn or otherwise reproduced in order to help determine his or her identity. In addition, the imagery can be displayed, published or broadcasted in media without concerns of being overly graphic.

An Unplanned Complex Suicide by Multiple Blank Cartridge Gunshots and Cutting

Blank firing guns are readily accessible in most countries due to an absence of legal regulations. These weapons are capable of causing lethal injuries. We report a rare case of secondary (unplanned) complex suicide committed with a knife and blank cartridge pistol. A 59‐year‐old man was found dead with three superficial incisions in his neck and a gunshot wound to the chest. The external examination revealed an entrance wound in the left chest region consistent with contact shooting. The appearance of a muzzle imprint suggested two discharges. The autopsy showed a slightly hemorrhaged but otherwise intact pericardium, blood in the pericardial sac, and a channel‐like defect in the anterior wall of the left cardiac ventricle. The cause of death was attributed to cardiac tamponade. To the best of our knowledge, this is the first reported case of unplanned complex suicide involving an unmodified blank firing gun.

Atypical stab injury suggesting ritual suicide

Sharp weapons have been one of the most common deadly tools in cases of homicide and suicide for a long time. Tentative incisions accompany the majority of suicides by sharp force and the absence of hesitation marks provokes questions about the manner of death. We present the bizarre fatality of a 41-year-old male with an isolated circumscribed incision on the right neck, where the body was found lying in a pool of blood in the shower of his apartment. The internal examination revealed a 4-cm-long channel-like defect running inwardly and downwardly along the right sternocleidomastoid region. The cause of death was external bleeding from an injured right carotid artery and internal jugular vein. The wound had clean non-contused margins without any conspicuous hesitation injuries. A fragment of a razor blade, found in blood splatters, was identified as the only potential injuring tool. The case was classified as a suicide.