Jeffries was a deputy police officer on Proxima 2.
Originally a Texas Republic State Trooper, he joined others to start a colony on Proxima 2. He became Ben Fuller's deputy.
After Samantha Jones got lost following a riot, she was found by Jeffries. He brought her back to police headquarters, where they discovered that Fuller had been killed and replaced by one of the Face-Eater's shapeshifters. It killed Jeffries, but Sam managed to escape. (PROSE: The Face-Eater)