How do forensic analysts determine bullet trajectory at a crime scene? In a new video from WIRED magazine, Matthew Steiner, a certified senior crime scene analyst and veteran investigator, explains how 3D laser scanning provides an invaluable approach for shooting reconstruction.
Using a Leica RTC360 and a bullet-riddled car door, Steiner shows how investigators can quickly capture precise measurements and angles for trajectory analysis. He notes that the laser scanner was set up in two different positions to scan the scene, and the data was then imported into Leica software to visualize the point cloud. He explains how all the details from the scene were captured at an ultra-fast speed of two million measurements per second.
“The beauty of laser scanning is that, unlike a static image, we can move it around,” Steiner says. “We can view it from different angles. We can see the trajectory rods that we have in place and get novel views of the scene that we couldn’t get with traditional video or photography.”
Steiner also walks viewers through the basics of ballistics, including internal, external and terminal ballistics. He shows the difference between a cartridge, casing and a bullet, as well as the deformation that occurs when the bullets strike different targets. He explains the directionality of bullets and how investigators determine the entrance and exit, as well as basic trajectory analysis techniques.
“One of the great things about laser scanning is that it’s objective,” Steiner says. “Any other type of measurements that we take at the crime scene, I’m choosing to measure from two or three points to this evidence. With the Leica scanner, anything that’s in its field of view is being documented.” This comprehensive approach ensures that all evidence is captured—even details that might not seem important at the time.
To learn more about how 3D laser scanning can assist your crime scene investigation, please contact us.