Age: 59.
Residence: Oakdale.
Job: Forensic science supervisor, Minnesota Bureau of Criminal Apprehension; oversees crime-scene program and divisions that analyze latent prints, firearms and tools, and documents.
Experience: 11 years at the BCA; four years at the police department in Wichita, Kan.; 20 years in the U.S. Air Force, including 16 as a criminal investigator.
Biggest case: The 1999 murder of Cally Jo Larsen, a 12-year-old girl from Waseca, Minn., who was killed after she interrupted a burglar in her home -- a case featured on "Forensic Files."
Comment: "We want to find the person who did this. And when you do, that's just gravy on top. It's a great motivator."
In person: Peterson and colleagues will appear at the Science Museum of Minnesota as part of its "Meet the Experts" series, 1-4 p.m. on Oct. 25, Nov. 22 and Dec. 20.
