The Ethics of Silence - Nash C. J.

A murder has occurred on Mars and Earth has sent an agent to immediately investigate.

Immediately is a relative term since the trip from Earth to Mars takes a minimum of eight and a half months. By the time Mason Turner arrives on Mars, most of the evidence has either been lost or destroyed, and the colonists refuse to cooperate with the investigation.

There are secrets on the red planet, secrets that could destroy the colony.