Rhett Shearon was born to family of marshals, as four generations of family before him had been lawmen. He was in charge of keeping law in Quijadas on the planet Choss. He became friends with Bill Bousquette, as Rhett admired the man's intense focus. He had a large collection of firearms that he kept, including an AGG-12 grenade launcher.
He raised Rin Shearon as if she were a son, training her to take over his role as marshal and using her as a deputy. She admired and looked up to him, and used him as a role model for her later life.
In 2501, the zerg attacked Bim Battum on Choss in a time known as "the troubles." In a month long conflict the Terran Dominion fought the zerg hives on the surface. Rhett Shearon lost his life in the battle, one of the few casualties the Dominion suffered before purifying the hives. Rin was left his collection of guns, and took over his role as marshal.