Is Joe Leaphorn the murderer?

Joe Leaphorn is a Navajo Tribal Police Lieutenant, who as well as being familiar with Navajo culture from his own heritage also holds a master's degree in anthropology from Arizona State University, something that enables him to understand the cultural patterns of both Navajo and Zuni as well as those of the bilagáana (white people). He is unusual as the protagonist of detective fiction in being a Native American and balancing his scientific and academic training with Navajo values concerning the land and community.
Leaphorn uses a combination of skill in tracking and in observing and assessing people to solve crimes. Far from being a murderer, he is a detective employed as a member of the Navajo police force. He blends compassion with a strong sense of justice, tracking down the real killer, Dr. Chester Reynolds, an embittered Anglo archaeologist.
https://www.nytimes.com/1989/05/14/magazine/navajo-cops-on-the-case.html