Tony Hillerman wrote 18 novels in a sequence covering Joe Leaphorn and Jim Chee of the Navajo Tribal Police. Pluto was the original publisher in the UK of the second novel "The Dance Hall of the Dead".
Hillerman's books initially featured Joe leaphorn but other key characters particularly Jim Chee were introduced over time.
The set of Navajo Tribal Police books is as below
Hillerman's books have been published and translated in many editions, see here. These are some nice Penguin editions.
The Navajo Tribal Police novels have been continued by his daughter Anne Hillerman.