Joel Chambers was a Vault 51 dweller who perished under ZAX's rule. A state senator who rose to prominence with the aid of his father, Chambers made one of the earliest bids for leadership in the Vault, only to fail when ZAX decided that voting could not produce a suitable Overseer candidate. Chambers tried to continue in an informal leadership role, especially as the food shortages worsened, leading to violence in the Vault. However, his relationship with Carmen Greene proved to be his undoing and his marriage unraveled.
In August, things came to a head. ZAX engineered a confrontation between them and their lovers, putting the four of them in one room and letting them kill one another: Elizabeth strangled Carmen, Joel's lover, Joel shot Matthew, Elizabeth's lover, and then the Chambers murdered each other.
Joel Chambers is mentioned only in Fallout 76.