Gun Chung is a technician with the Los Angeles Police Department's Firearm Analysis Unit.
In 2014, he helped Open-Unsolved Unit detectives Harry Bosch and Lucia Soto to analyze a slug recovered from the spine of the newly-deceased Orlando Merced. Although Chung could not specify the individual weapon that fired the bullet in question, he concluded that the bullet was a Remington .308 soft nose and that it was fired by a Kimber Model 84 hunting rifle. His information was important to the direction of the investigation because it had previously been assumed that the bullet was from a handgun that had been fired by a local gang member. The use of a hunting rifle began to suggest something more like a sniper, meaning that it was unlikely to be a random shooting.