[S5E4] Penance
Johnson wasn't a Belter by birth. He served as a Colonel in Earth's U.N. Navy until a botched operation led to the deaths of thousands of Belters. He was then convinced by OPA leader Anderson Dawes to join the Belter's cause as a form of penance. Many were wary of his loyalties, but Johnson proved his hardcore dedication to the Belt. He was employed, in part, to help the OPA become a legitimately recognized government; Johnson was still considered a hero on Earth and he could help other Earthers see that the people of the Belt weren't the violent criminals they were painted as.
[S5E4] Penance
The team takes up the case of a homeless man who was accidentally burned by a miniature rocket launched by two boys in a local park. The patient's most striking symptom is confusing various smells (e.g. body odor for peppermint). He also hides his real name and other information, saying that he does not want his abusive father to be drawn into the case. Now that he can fight back, he is afraid that he might kill his father, who apparently abused him as a child by putting out cigarettes on his body. Masters shows sympathy towards the patient due to his desire to do penance for his past deeds and his aspirations of becoming a doctor. 041b061a72