The relevance of current forensic firearms examination techniques when applied to 3D printed firearms

This research project had two major objectives. The first was to successfully print and fire the Liberator, a 3D-printed firearm, to assess its feasibility as a lethal weapon. The second objective was to identify any individual characteristics that might be deposited during the firing process by the firearm. The Liberator was printed using unchanged files downloaded from the internet using PLA and ABS filament. The Liberator was fired remotely into newspapers at the Allegheny County Medical Examiner's Office. The printing of the Liberator was both inexpensive and relatively quick with only minor hand modifications made after printing. The Liberator fractured beyond repair after firing but successfully fired and penetrated three newspapers. Neither the bullet nor the cartridge case exhibited any individual characteristics that could be used for identification purposes. Suspected thermoplastic deposits were identified on both the bullet and cartridge case, but additional testing must be done for confirmation purposes. In conclusion, the Liberator can be used reliably for one shot and will not yield any evidence for Firearms and Toolmark Examination.