A survey of case studies on the use of forensic three-dimensional printing in England and Wales

Abstract

3D printing has rapidly developed and been applied in forensic science due to its use in creating demonstrations for courts of law. Much of the literature on this specific topic has focused on the use of 3D printed models in academia, the potential influence on a jury, and its use as a long-term documentation process, but with few actual forensic case examples. This paper offers an insight into the development of 3D printing in forensic practice and how 3D printing is currently being used in the criminal justice system in England and Wales.A series of case reports were gathered from multiple police forces and forensic practitioners in the UK to identify how 3D printing was being used. These discussions established who was requesting 3D printed exhibits, what type of technologies were being utilised, what type of exhibits were being printed, and resulting feedback for the use of 3D printed material within a criminal case. As a result, this research demonstrates the current use of 3D printing in England and Wales, discussing the associated cases that have been known to incorporate 3D prints. Likewise, this work explores the limitations that have been encountered by forensic practitioners and identifies a series of research questions that should be considered in future investigations.

Keywords: 3D Imaging; Blunt force trauma; Dismemberment; Forensic science; Human remains; Visual evidence.

Fig. 1

Chart illustrating the types of cases recorded (n = 17)

Fig. 2

Clockwise from top right, charts illustrating the count from n = 16 cases for: the type of print material used; whether the print was presented in court as a visual aid; the size of the print (1:1 ratio); the material/evidence types

Fig. 3

Two examples of 3D printed replicas from cases of fatal cranial injury (A) depression fracture to the right supraorbital region (B) fracture void on the left parietal bone

Fig. 4

Image taken from a supporting booklet showing different views of a rendered 3D model of an infant cranium exhibiting parietal fracture on both sides

Fig. 5

3D printed model examples from two non-fatal cranial injury cases. Case example 7: depression fractures to the frontal bone and nasal region in an adult. Case example 8, fracture spanning the right temporal and parietal bones (highlighted in red) in an adult.

Fig. 6

Image taken from a supporting booklet from case 9: the post-surgery 3D model can be seen prior to printing

Fig. 7

A series of 3D prints examples from case 10, a dismemberment case where the partially dismembered bone samples were 3D printed. (A) Print of false start kerf, (B) A micro-CT model of the humerus dismemberment site with numerous shallow kerf marks (C) A series of 3 images of the three, 3D printed, partially dismembered lumbar vertebrae from oblique (left), frontal (middle), and lateral (right) views

Fig. 8

Case 11, a dismemberment case where partially dismembered bone samples and the saw blade were 3D printed. Left, a 3D print of near complete false start kerf with blade print inserted into the voided area, and right, a cross-sectional view, (Insert) tooth pattern of blade demonstrated in 3D print

Fig. 9

Virtual and 3D printed replicas of the freezer and pseudo-dismembered body, demonstrating the theoretical fit of the components in such a space

Fig. 10

A partially mummified human foot that was documented and 3D printed to ensure the actual human remains were not contaminated or exposed to further decomposition

Fig. 11

3D printed weapons or artefacts. (a) A projectile that was documented in situ and printed prior recovery from the body. (b) A knife that was scanned in a sealed container and printed without being removed.

Fig. 12

A 3D printed maxilla from a burned individual that was not subjected to further physical alterations. The 3D printed model still allowed for an identification to be made