Cougar's Cache. Gabriel Hawke Novel, #12

This double cold case and current homicide have Oregon State Police Fish and Wildlife Trooper Gabriel Hawke calling in favors. and exploring a childhood he shoved into the deep recesses of his mind.  While patrolling on the Snake River in Hells Canyon, Gabriel Hawke's dog digs up a human bone. Hawke is confronted by an aunt he doesn't remember, and he finds a canister of film when the rest of the remains are excavated.
The film shows someone being killed and a rifle pointed at the photographer. Going through missing person files, Hawke discovers the victims of the decades-old double homicide. A person connected to the original crime is murdered, giving Hawke more leads and multiple suspects. Attending a local Powwow with his family, Hawke discovers more about his childhood and realizes his suspects have been misleading him.