Talking God by Tony Hillerman

A grave robber and a corpse reunite Navajo Tribal Police Lt. Joe Leaphorn and Officer Jim Chee. As Leaphorn seeks the identity of a murder victim, Chee is arresting Smithsonian conservator Henry Highhawk for ransacking the sacred bones of his ancestors. As the layers of each case are peeled away, it becomes shockingly clear that they are connected, that there are mysterious others pursuing Highhawk, and that Leaphorn and Chee have entered into the dangerous arena of superstition, ancient ceremony, and living gods.