"Boz" was struck and killed by a motorist Dec. 27 on Petaluma Hill Road south of Santa Rosa city limits, police Lt. John Noland said.
The dog left a fenced yard and ended up on the road, Noland said. The driver did not remain at the scene of the accident.
Boz, an eight-year-old Belgian Malinois, worked with a handler for more than five and a half years. He responded to thousands of calls for service in Santa Rosa and Sonoma County, Noland said.
Boz was a trained patrol canine and was certified in drug detection.
Anyone who witnessed the hit-and-run incident is asked to call CHP Officer Shawn Hopkins at (707) 588-1400.