In a field where every imprint matters, a Bowling Green State University (BGSU) graduate student is helping refine forensic investigators’ analysis of randomly acquired characteristics (RAC) on footwear impressions.
Katie Roy graduated from BGSU in 2025 with a bachelor’s degree in forensic science and is currently a master’s student in forensic science, working on her thesis project about RACs on footwear impressions.
“My [internship] supervisor brought up that there are some gaps in knowledge in the forensic footwear kind of subsection. So, I ended up poking around my senior year during a capstone class that I had to take at BGSU,” Roy said. “I wrote a paper identifying the weaknesses in forensic footwear comparison and from there, I identified that there is a gap of knowledge in forensic randomly acquired characteristics.”
RAC is like fingerprints for your feet. There could be rocks, dirt or gum in your shoe that a forensic scientist could see.
“So, randomly acquired characteristics are very specific points of damage or lodged debris. There’s general wear that happens on your shoe,” she explained. “We are not looking at that, we are looking at specific cuts, tears and lodged debris that are easily identifiable and can be compared from an unknown impression to a source shoe.”
Some studies of RACs on footwear use different types of shoes and sizes that are not unisex in their databases, but Roy is studying the same type of shoes that are unisex.
“So with the study that I’m doing, I have all of the same kind of shoes, which helps keep those class characteristics the same. So I have the same tread design. They were worn for about the same time by the same amount of people doing the same things, and that is extremely good to come by,” Roy said.
Roy had her thesis project decided; she just needed the help of the FMB to make it happen.
“He [FMB Director Jon Waters] said, ‘Yeah, I think that’s really cool that you want to do that.’ I had a couple of meetings with them over Zoom over the summer just to work out the possibility of us actually doing it,” she said. “I looked at the FMB schedule, found the first weekend where they did not have a game and basically asked that weekend be reserved for me. They agreed. Sept. 20 to 21 was when we printed the shoes.”
Roy got over 100 pairs of shoes from the FMB, which is considered the largest non-standardized sample.
“It hasn’t been done in any other samples before. I managed to collect 121 pairs. It’s the largest non-normalized sample that I have been able to find. So the other largest sample size, up to this point, that was non-normalized was 39 pairs,” Roy said.
After collecting the shoes from the FMB, Roy and some master’s students, whom Roy asked to help, set up the forensic science laboratory to get the impressions.
“We actually set up the whole lab to be different stations. We had people labeling the shoes, giving them identification numbers and codes, photographing them, dusting the impressions and printing them and then cleaning them, labeling them and putting them in boxes for return,” she said.
Caleb Edwards-Dugan, a volunteer who helped Roy with her project, worked on Sept. 20 for about eight hours putting the powder on the shoes.
“I was tasked with putting the fingerprint powder on the shoes, making sure that there was a sufficient amount but not enough to where it was like flooded on the paper and then I would hand those to Katie to print them,” Edwards-Dugan said.
Mary Kate Dooley is another volunteer who helped Roy on Sept. 21, for about seven hours, cleaning the shoes once they were finished.
“[We used] nail brushes and she also had these sponges that you could use to wash them. So it was just to get the remaining black powder off of them, because that stuff tracks everywhere,” Dooley said.
Roy then returned the shoes to the FMB, but she wanted to give the FMB something for helping her.
“I felt really bad that I could not compensate the FMB really. I couldn’t give them money. I couldn’t give them anything. I ended up working with the university to give one service hour to every FMB member who donated their shoes,” she said.
With the results of the FMB impressions, Roy is looking to add to the forensic science community.
“In forensic science, it’s really important to have a foundational validity backing the science that you do. Without that foundational validity, the fact that your analysis is valid and that you have researched supporting it,” Roy said. “That’s the most important thing, because your evidence could determine whether somebody goes to prison or not, and how severe their sentence is. I’m hoping that my research will be able to add to that foundational validity and will help forensic experts with their testimony in court.”
Roy is grateful to everyone who helped with her project and is excited to see where it goes.
“This project literally wouldn’t have been able to happen without the FMB, so I’m forever grateful for them. Of course, all the professors have helped a lot, too,” Roy said. “It will get published through OhioLink and then I’m hoping to publish it in the Journal of Forensic Sciences or Forensic Science International.”
