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Goia S, Cooper G, Norman DG, Primeau C, Hall M, Hawley J, Williams MA. The use of micro-CT in the investigation of a case involving 3D printed firearms. Forensic Sci Int 2024; 363:112157. [PMID: 39106595 DOI: 10.1016/j.forsciint.2024.112157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Revised: 05/09/2024] [Accepted: 07/22/2024] [Indexed: 08/09/2024]
Abstract
This paper highlights how micro-CT was used to assist in the investigation of hybrid firearms constructed using a mixture of plastic and metal components, as a complementary technique to the physical examination performed by firearms experts. In recent years, there has been an increase in the complexity and sophistication of 3D printed and hybrid firearm designs. This was also the case in the investigation presented herein, with the firearms seized demonstrating a step change in the threat level they pose through their complexity. Thus, we describe how data produced from micro-CT scans was used to help firearms experts study the viability and mechanics of two hybrid weapons prior to dismantling and test-firing. This process aided experts in determining whether components were 3D printed or manufactured through other means, whilst ensuring that a digital record (digital twin) was retained in case evidence was damaged during testing. Finally, we show how the data was presented visually through animations and as evidence in court. This proved to be imperative when communicating to the judge, jury, and wider investigating teams, the complex multiple components and mechanisms within the firearms.
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Affiliation(s)
- Sofia Goia
- Forensic Centre for Digital Scanning and 3D Printing, WMG, University of Warwick, Coventry CV4 7AL, UK.
| | - Gareth Cooper
- West Midlands Police, Lloyd House, Birmingham B4 6NQ, UK
| | - Danielle G Norman
- Forensic Centre for Digital Scanning and 3D Printing, WMG, University of Warwick, Coventry CV4 7AL, UK
| | - Charlotte Primeau
- Forensic Centre for Digital Scanning and 3D Printing, WMG, University of Warwick, Coventry CV4 7AL, UK
| | - Michael Hall
- West Midlands Police, Lloyd House, Birmingham B4 6NQ, UK
| | - Julian Hawley
- West Midlands Police, Lloyd House, Birmingham B4 6NQ, UK
| | - Mark A Williams
- Forensic Centre for Digital Scanning and 3D Printing, WMG, University of Warwick, Coventry CV4 7AL, UK
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Falardeau MS, Mireault C, Daoust B, Muehlethaler C. Chemical analysis of polymers used for 3D printing of firearms. Forensic Sci Int 2024; 357:111999. [PMID: 38518568 DOI: 10.1016/j.forsciint.2024.111999] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Revised: 02/01/2024] [Accepted: 03/17/2024] [Indexed: 03/24/2024]
Abstract
3D-printed firearms cause challenges in criminal investigations and forensic analysis because they are difficult to trace. Indeed, in addition to being "ghost guns", they may not produce all the conventional ballistic traces normally used for firearm identification. However, 3D-printed firearms produce other very specific traces, such as polymer traces which come from the polymers used to print the firearm. To date, only a few studies have focused on the analysis of polymer traces. This study therefore aims to characterize polymer traces from 3D-printed firearms, using non-destructive spectroscopic techniques readily available in most forensic laboratories (i.e., FTIR and Raman) and evaluate the potential for association of polymer specimens or traces with their source. To do so, the study was divided into four parts. First, the population study conducted among 3D printing companies and individuals practicing 3D printing has revealed that PLA and PLA+ are the most widely used polymer types in Quebec, Canada. Second, FTIR and Raman spectroscopic analysis of polymer samples collected during the population study has allowed the development of a reference polymer spectral database. The analysis and interpretation of these spectra revealed that polymer filaments present very low intravariability, but very high intervariability, due in part to the different polymer types and the pigments used to color them. The use of chemometric tools with the spectra showed that these two spectroscopic methods were highly discriminating. Third, test firing of 3D-printed firearms has allowed for the simulation of a scene involving this type of firearm and the collection of polymer traces generated. Fourth, the comparison of chemical signatures between polymer filaments and polymer traces has allowed for the evaluation of the potential for chemical association. This study highlights the added value of chemical analysis of 3D-printed firearms polymer traces in a criminal investigation by demonstrating that polymer filaments, the polymer from which a 3D-printed firearm is made, as well as polymer traces generated during firing, can be linked chemically and provide relevant information.
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Affiliation(s)
- Mylène S Falardeau
- Laboratoire de Sciences Judiciaires et de Médecine Légale, Department of Ballistics, 1701 Parthenais Street, Montréal, Québec H2K 3S7, Canada; Université du Québec à Trois-Rivières, Department of Chemistry, Biochemistry and Physics, 3351 Des Forges Blvd., Trois-Rivières, Québec G9A 5H7, Canada; Université du Québec à Trois-Rivières, Groupe de Recherche en Science Forensique, 3351 Des Forges Blvd., Trois-Rivières, Québec G9A 5H7, Canada.
| | - Caroline Mireault
- Laboratoire de Sciences Judiciaires et de Médecine Légale, Department of Chemistry, 1701 Parthenais Street, Montréal, Québec H2K 3S7, Canada
| | - Benoit Daoust
- Université du Québec à Trois-Rivières, Department of Chemistry, Biochemistry and Physics, 3351 Des Forges Blvd., Trois-Rivières, Québec G9A 5H7, Canada; Université du Québec à Trois-Rivières, Groupe de Recherche en Science Forensique, 3351 Des Forges Blvd., Trois-Rivières, Québec G9A 5H7, Canada
| | - Cyril Muehlethaler
- Université du Québec à Trois-Rivières, Department of Chemistry, Biochemistry and Physics, 3351 Des Forges Blvd., Trois-Rivières, Québec G9A 5H7, Canada; Université du Québec à Trois-Rivières, Groupe de Recherche en Science Forensique, 3351 Des Forges Blvd., Trois-Rivières, Québec G9A 5H7, Canada; Centre International de Criminologie Comparée, PO Box 6128, Station Centre-ville, Montréal, Québec H3C 3J7, Canada
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Schaufelbühl S, Florquin N, Werner D, Delémont O. The emergence of 3D-printed firearms: An analysis of media and law enforcement reports. Forensic Sci Int Synerg 2024; 8:100464. [PMID: 38584608 PMCID: PMC10998078 DOI: 10.1016/j.fsisyn.2024.100464] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2023] [Revised: 02/27/2024] [Accepted: 03/15/2024] [Indexed: 04/09/2024]
Abstract
3D-printed firearms, an emerging category of privately made firearms (PMF) produced beyond government control, have become increasingly prevalent due to technological advancements. They are now emerging as a cost-effective and reliable alternative to conventional firearms. Raised to public awareness following the 2013 release of the 3D-printed Liberator, these firearms are now more commonly encountered by police forces. This article analyses various reports involving 3D-printed firearms, reflecting the increasing encounters by law enforcement agencies. It examines 186 cases involving 3D-printed firearms, primarily from North America, Europe, and Oceania, highlighting a significant rise in incidents since 2021. These incidents include seizures, illicit uses, and online sales, with the firearms typically being hybrid models, Parts Kit Completions/Conversions (PKC), or firearm components such as auto sears. The study underscores the use of affordable equipment and materials for production, emphasizing the accessibility and potential risks of these firearms.
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Affiliation(s)
| | - Nicolas Florquin
- Small Arms Survey, Graduate Institute of International and Development Studies, Geneva, Switzerland
| | - Denis Werner
- Department of Chemistry, Biochemistry and Physics, Université du Québec à Trois-Rivières, Canada
- Groupe de Recherche en Science Forensique (GRSF), Trois-Rivières, Québec, Canada
| | - Olivier Delémont
- Ecole des Sciences criminelles, University of Lausanne, Switzerland
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Shim BS, Hou JU. Improving Estimation of Layer Thickness and Identification of Slicer for 3D Printing Forensics. SENSORS (BASEL, SWITZERLAND) 2023; 23:8250. [PMID: 37837079 PMCID: PMC10575098 DOI: 10.3390/s23198250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Revised: 09/26/2023] [Accepted: 09/28/2023] [Indexed: 10/15/2023]
Abstract
This study emphasizes the significance of estimating the layer thickness and identifying slicer programs in the realm of 3D printing forensics. With the progress in 3D printing technology, precise estimation of the layer thickness has become crucial. However, previous research on layer thickness estimation has mainly treated the problem as a classification task, which is inadequate for continuous layer thickness parameters. Furthermore, previous studies have concentrated on hardware-based printer identification, but the identification of slicer programs through 3D objects is a vital aspect of the software domain and can provide valuable clues for 3D printing forensics. In this study, a regression-based approach utilizing a vision transformer model was proposed. Experiments conducted on the SI3DP++ dataset demonstrated that the proposed model could handle a broad range of data and outperform the current classification models. Additionally, this study proposed a new research direction by introducing slicer program identification, which significantly contributes to the field of 3D printing forensics.
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Affiliation(s)
| | - Jong-Uk Hou
- Division of Software, Hallym University, Chuncheon 24252, Republic of Korea;
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Szwed A, Schaufelbühl S, Gallusser A, Werner D, Delémont O. Was a 3D-printed firearm discharged? Study of traces produced by the use of six fully 3D-printed firearms. Forensic Sci Int 2023; 348:111736. [PMID: 37269623 DOI: 10.1016/j.forsciint.2023.111736] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Revised: 03/30/2023] [Accepted: 05/19/2023] [Indexed: 06/05/2023]
Abstract
Since the blueprints of the Liberator were published and successfully tested, countless new designs for said 3D-printed firearms and 3D-printed firearm components have been created and made publicly available. These new 3D-printed firearms, which are praised by their designers as ever more reliable, can be found on the Internet with little effort. Press reports have shown that various models of 3D-printed firearms have already been confiscated by law enforcement services around the world. So far, forensic studies have addressed this set of problems relatively little, whereby for the most part only the Liberator has been examined in detail and three other designs were only included a few times. The rapid pace of this development poses new challenges for forensic investigations and unveil new spheres of investigation regarding 3D-printed firearms. This research initiative aims to determine whether the results from previous studies on Liberators, are also reproducible and observable when using other models of 3D-printed firearms. In this respect six fully 3D-printed firearms - PM422 Songbird, PM522 Washbear, TREVOR, TESSA, Marvel Revolver and Grizzly - were produced on a material extrusion type Prusa i3 MK3S using PLA as the material. Test firings of these 3D-printed firearms have shown that they are indeed functional, but that, depending on the model, they suffer different levels of damage when fired. However, they were all rendered inoperative after one discharge and could not be used for further discharges unless the broken pieces were replaced. As in other studies, the firing process and the resulting ruptures on the 3D-printed firearm, projected polymer parts and fragments of different sizes and in different quantities into the immediate environment. The parts could be physically matched, allowing the reconstruction and identification of the 3D-printed firearms. Elements of ammunition also showed traces of melted polymer on the surface and cartridge cases bore tears or swellings.
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Affiliation(s)
- Aurélie Szwed
- Ecole des sciences criminelles, University of Lausanne, Switzerland; National Institute of Criminalistics and Criminology, Brussels, Belgium
| | | | - Alain Gallusser
- Ecole des sciences criminelles, University of Lausanne, Switzerland
| | - Denis Werner
- Ecole des sciences criminelles, University of Lausanne, Switzerland; Discipline of Biomedical & Forensic Science, School of Human Sciences, University of Derby, United Kingdom
| | - Olivier Delémont
- Ecole des sciences criminelles, University of Lausanne, Switzerland.
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Mattijssen EJ, Kerkhoff W, Hermsen R, Hes RA. Interpol review of forensic firearm examination 2019-2022. Forensic Sci Int Synerg 2022; 6:100305. [PMID: 36569454 PMCID: PMC9772807 DOI: 10.1016/j.fsisyn.2022.100305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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Maillard M, Chevalier J, Gremillard L, Baeza GP, Courtial EJ, Marion S, Garnier V. Optimization of mechanical properties of robocast alumina parts through control of the paste rheology. Ann Ital Chir 2022. [DOI: 10.1016/j.jeurceramsoc.2022.12.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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