The Judge Who Ran Out of Mercy.
Every decision you make depletes your capacity for the next one. The science on this is not subtle.
A study of 1,112 parole hearings found that the law mattered less than the time of day.
In 2011, three researchers published a study in the Proceedings of the National Academy of Sciences. They had spent months tracking 1,112 parole hearings in Israeli courts, recording the outcome of each case alongside one variable most legal scholars would consider irrelevant: what time of day the hearing took place.
The results were uncomfortable.
At the start of each session, judges approved parole roughly 65% of the time. As the session progressed, that figure fell, steadily, predictably, with no correlation to the severity of the crime or the length of the sentence. By the end of each session, the approval rate had dropped to nearly zero.
Then the judges took a food break. Approval rates reset immediately to 65%.1
The researchers called these extraneous factors in judicial decisions. What they had found was that the law, with all its protocols and precedents and professional training, was being quietly overridden by something as basic as how many decisions a person had already made that morning.
The mechanism is called decision fatigue. Every decision, regardless of its significance, draws from the same cognitive resource. A judge choosing between granting and denying parole. A person standing in a supermarket aisle choosing between 127 coffees. The resource does not distinguish between them. It simply depletes. The system that manufactures this depletion daily was not an accident.
When it runs low, the mind defaults to the easiest available answer. For a judge, the easiest answer is denial, maintain the status quo, defer the complexity. For a shopper, the easiest answer is to grab the familiar brand, the one at eye level, the one with the most shelf space. Neither decision is really a decision. It is the absence of one.
Now consider your week. The average person makes around 226 food-related decisions every single day. By the time you have navigated a full supermarket shop, compared prices on your phone, scrolled through an Amazon recommendation engine and made it home, you are sitting down to the people and the work that deserve the most from you with the least left to give.
The captive whose case was heard at the end of the session did not receive less justice because of what they had done.
They received less justice because of what the judge had already been asked to do that day.
The single most powerful predictor of whether they went free was not what they had been charged of. It was when their case was heard.
1 Danziger, S., Levav, J., & Avnaim-Pesso, L. (2011). Extraneous factors in judicial decisions. Proceedings of the National Academy of Sciences, 108(17), 6889–6892.
