4 ideas
Benjamin Malaussène is nominally a 'technical quality controller' at a Paris department store, but his real job is to be summoned whenever a customer complains about a defective purchase. His boss publicly berates him as the culprit, and Benjamin performs such abject distress, including hints that he'll be fired or harm himself, that the customer, overcome with pity, withdraws the complaint and the store avoids paying a refund.
An institution can neutralize legitimate grievances by giving them a suffering human face to land on. When the complainant sees that pressing the claim will visibly punish a vulnerable individual, the moral cost of justice shifts onto them, and they drop the claim. The organization's liability is converted into the customer's guilt.
Once a person's function is to absorb fault, others stop checking whether he is actually guilty, and his proximity to trouble reads as evidence rather than coincidence. The scapegoat role follows its holder beyond the context it was designed for.
Benjamin plays the same role at home as at work. He raises a crowd of half-siblings left by an absent mother and absorbs the family's chaos and blame so the others can function. Read this way, being the scapegoat is a disposition toward carrying others' burdens, and the job simply prices a trait he already has.