An Immersive Learning Experience for Forensics Students
This article contains discussions of firearm components and gun violence.
John Z. Wang, PhD, is a Forensic Studies Professor at the School of Criminology, Criminal Justice, and Emergency Management. For Week of RSCA 2025, he transformed USU-304 into an immersive learning simulator to demonstrate his research, which focused on identifying recycled casings, one of the critical issues at a shooting related scene. A recycled casing is the one with which the primer has been removed and a new primer recapped, and new gun powder refilled. As a result, the new cartridge possesses more than two extractor and ejector marks and it is extremely difficult to identify which extractor and ejector is responsible for the shooting in question. Dr. Wang demonstrated the steps of identifying such a fired casing at the mock scene with a portable devise. As an example, he also simulated an event of an on-campus shooter.
Dr. Wang first placed three evidence markers 1, 2, and 3 across the room for the three “active shooting scenes.” He then challenged the 30 student attendees with a series of objectives:
- What type of weapons fired these casings?
- How many guns were involved?
- Among the four casings, which one is the most challenging to connect to a specific gun? Why?
After briefly reviewing the different types of weapons, the students jumped right into the action by examining each fired casing on the floor. The room was filled with spirit as groups began to analyze the differences between each casing.
In this hands-on exercise, the students were able to get up close and personal. They took pictures, felt the grooves in their hands, and looked at anything that seemed irregular. To the average eye, tiny scratch marks and scuffs might be unnoticeable; however, forensic students noted that a single metal scuff mark around the primer can be the key of identifying the key evidence: a recycled casing, using their cellphone camera.
These challenges helped the students not only understand the research but also gain a hands-on experience for themselves; recycled casings are much harder for crime scene technicians to match the firearms that fired them. These casings can cause major disruptions in both evidence examination in general and a cross-examination at trial in particular.
Before they discussed the answers, Dr. Wang took a moment to instruct the students about the surviving tips during a mass shooting from a CSU training video. He reminded everyone that there are three life-saving words: run, hide, fight. Students felt this information was crucial to a safer community. Dr. Wang further reviewed the safety training video across all Cal State campuses and screened the “CSULB Active Shooter Training Video.”
Deliberation continued after the screening. The students were eager to find out the answers. Some students used their knowledge from Dr. Wang’s own forensic classes to make a prediction.
“I think what really helps me in class is good study habits and a hands-on exercise approach, but you can really tell that the professor is enthusiastic about his work,” a student said.
To conclude his Week of RSCA presentation, he gathered each casing from the evidence markers and projected them onto a screen using a state-of-the-art microscope.
Dr. Wang checked some of the work from his students. After much debate and analysis, the answers were revealed. He explained the intricacies of pistol retraction, how and why four guns were involved, and delved deeper into the way different guns (such as revolvers, pistol by Glock, rifles, and shotguns) make unique marks in comparison to the recycled casing. Forensic students felt empowered knowing that these are the real-world problems they’d be facing and solving as they are making transition into the field of crime scene forensics.
Dr. Wang’s research was supported by the 2023-2024 CHHS RASC Grant.
