The field of forensics is concerned with “the application of the scientific method to help the judicial system or common good of society” (Forensics, 2008). The scientist must be impartial, utilizing the scientific method in order to determine the likelihood of a certain situation coming to pass or as a means of testing out basic hypotheses formulated as a result of collected evidence (Forensics, 2008). There are many different areas of forensic research that an individual might decide on for their career choice, but perhaps one of the most interesting is that of the firearm and toolmark examiner. In order to determine whether or not this is the right career path for an individual, it is important that they are made aware not only of what the job description entails, but understanding the role that the firearms examiner plays in the investigation and their relationship to the forensic process.
The firearms and toolmarks examiner is primarily responsible for determining whether or not “a bullet, cartridge case, or other ammunition component was fired in or cycled through a specific firearm to the exclusion of all other firearms” (State of Arkansas, 2011, p. 1; AFTE Certification Examinations, 2014). In addition to this responsibility, the examiner offers other services including “firearm function testing, general rifling characteristics, distance determination, serial number restoration, NIBIN (National Integrated Ballistic Information Network) database entry and searches, operation shutdown (test firing and NIBIN database entry), toolmark examination, (and) fracture matches” (State of Arkansas, 2011, p. 1; AFTE Certification Examinations, 2014).
Firearm identification is concerned, primarily, with the “comparison analysis of projectiles and cartridge cases found at crime scenes to submitted suspected firearms” (International Association for Identification, 2014, p. 1). What this means is that the initial sample is analyzed to determine the specific markings that are to be found on the evidence, paying particular attention to not only the striations present, but any kind of beveling, nicks, additional grooves, and other identifying marks as a means of working to ensure that when a weapon is found that was suspected to have been used in the commission of the crime, the weapon may be tested to look for those same striations and imperfections as a means of matching up the projectile with the weapon and conclusively tying the weapon, and its subsequent owner, to the crime itself.
Toolmark identification is a similar process, one whose primary difference is the absence of gunpowder as a means of discharging the projectile. Toolmark examination requires the examiner to determine the types of marks, and any subsequent imperfections present, made on the identified surface (International Association for Identification, 2014). The toolmark is then identified based on first the type of tool that was used to make the mark and then, when a suspect tool is found, the mark is compared to the mark made by the suspect tool in order to determine whether or not that specific tool was the one used in the commission of the crime (International Association for Identification, 2014). As tools get used during the course of daily activities, they generate various nicks and imperfections in their surface. Some of those nicks and imperfections may be visible to the naked eye, while others might require a microscope in order to identify, but regardless of the size of the imperfection, no tool has the same wear pattern as another, working to make a scientific match between a mark left on a particular surface and a specific tool a cinch, as long as the tool may be found; if the tool cannot be found, the examiner may only be able to determine the type of tool that made the mark.
In addition to the lab work required of the firearms and toolmarks examiner, the examiner may also be required to go out into the field and process the crime scene as a CSI (crime scene technician), collecting and preserving evidence for examination back at the lab at a later point and time (AFTE Certification Examinations, 2014). Regardless of whether the examiner goes out into the field to collect their own evidence or whether the evidence is brought to them in the lab, they are responsible for applying the scientific method in order to obtain the results of the tests, evaluate those results, and interpret the data obtained (AFTE Certification Examinations, 2014). Once the data has been successfully analyzed, the examiner will then be responsible for writing up their findings in a report and presenting that information to the officer in charge of the case (AFTE Certification Examinations, 2014). If the case ends up going to trial, the examiner may be called on at that point and time to testify about the results obtained, how those results were obtained, and the validity of those results (AFTE Certification Examinations, 2014). In addition to all of these tasks, the examiner is also responsible for staying up to date on all current research, studies, and practices that may work to improve their job proficiency or offer new or improved techniques that may serve to increase the validity of the tests or results and reduce the overall margin for error (AFTE Certification Examinations, 2014).
The firearms and toolmarks examiner is an essential part of a criminal investigation, dealing with a highly specialized level of forensics and requiring a full body of knowledge regarding the different types of firearms, the different tools, and the different markings and patterns that may be present, along with all of the associated accoutrements and parts of those different weapons or potential weapons. The job requires a highly specialized knowledge base, intense dedication to the work, and a minute attention to detail, making it one of the more specialized jobs in forensics, and one of the most fun.
- AFTE Certification Examinations. (2014). Job Description of the Firearm and Toolmark Examiner Classification. Retrieved 25 September 2014, from http://www.afte.org/AssociationInfo/certification/Files/Appendix%20A.pdf
- Forensicsguy.com. (2008). Forensics. Retrieved 25 September 2014, from http://www.forensicsguy.com/fornesics/forensics.html
- International Association for Identification. (2014). Firearms/Tool Mark Examination. Retrieved 25 September 2014, from https://www.theiai.org/disciplines/firearms_toolmark/
- State of Arkansas. (2011). ASCL: Firearms / Toolmarks. Retrieved 25 September 2014, from http://www.crimelab.arkansas.gov/sectionInfo/Pages/FirearmsToolmarks.aspx