The dog was riding in former chief Steve Harris' SUV when a pickup truck collided with the vehicle, killing Harris and severely injuring his wife, Margaret.
Sunday night's accident also claimed the life of a 16-year-old boy driving the pickup.
"We're hurting right now and just trying to support each other," said Redmond's current chief, Ron Gibson. "But it would be a tremendous comfort to the family to know and have the dog back, or even just to have closure knowing what's happened to the dog."
His name is Jake and he's a wirehaired pointing Griffon.
"Chief Harris was an avid hunter," said Gibson. "He had dogs throughout his life that he would train and take bird hunting. It was big part of who he was."
Officers have searched the crash site area around Redmond-Fall City Road and 244th Ave. NE and alerted neighbors.
Police say Jake has a collar and a microchip implant that would allow most veterinarians and animal shelters to identify him.
"We don't know if he was ejected from the vehicle and he's fine or if he's injured," Gibson said.
Anyone who thinks they've picked up Jake or seen him should contact Redmond Police Commander Shari Francois (425) 556-2500.