The Economist has published a fascinating article in its Science and Technology Section on the possible relationship between when a decision maker has a snack and the likelihood of him granting an application.
The study in the Proceedings of the National Academy of Sciences followed eight Israeli judges for then months as they ruled on over 1,000 applications made by prisoners to parole boards. As shown in the graph, the judges tended to grant favorable rulings early in the morning. As the hours passed, that number fell sharply, eventually reaching zero. After the judges had a meal break, however, the approval rate shot up back to its original value, before falling again as the day wore on.
The study offered two hypothesis for this somewhat disturbing trend for those who believe that justice should be blind. The first is that blood-sugar level is the crucial variable, and that decision makers become irritable as their blood-sugar level decreases.
The second is that it is not necessarily meals that matter, but rather that as the number of decisions made increases, decision makers begin to get tired and start looking for easy, status-quo preserving answers.
There is little of course that people appearing before decision makers can do to control this variable. Knowing and anticipating this trend, however, and remembering that decision makers are above all human, can be quite useful.