A communications director sends an ill-advised tweet before boarding a plane. A dentist kills a lion. Donald Trump says pretty much anything. In all of these cases, the Internet ratchets itself into a dervish of judgment, outrage, and opprobrium. To some, this repeated pattern of online shaming is a sign of mob behavior gone horribly wrong; to others, it’s a sign of social progress and underrepresented voices finally being heard. But to Jillian Jordan from Yale University, it’s a clue about a universal human behavior called third-party punishment.
Third-party punishment happens when we punish people who behave badly and violate social rules, even when their actions don’t directly affect us. All cultures show it to varying degrees (while chimpanzees do not). It starts early: eight-month-old babies will gravitate towards a nasty moose if it punishes an unhelpful elephant. And it usually comes with costs: whistleblowers risk their careers, protesters face arrest and beatings, people sending disapproving tweets can get doxxed and harassed, and more generally, punishers lose time, energy, and social relationships.
So why bother? Why censure someone who hasn’t harmed us directly?
Some scientists have suggested that it helps to cement human societies together by enforcing social norms and discouraging selfishness or bad behavior. As such, groups that practice third-party punishment should do better than those that do not. That may be true, but collective benefits don’t explain why individuals choose to incur the cost of punishment. Why doesn’t any one person just sit back and let others punish?