Inside the judicial mind

The quality of the judicial system depends upon the quality of decisions th at judges make. Even the most talented and dedicated judges surely commit o ccasional mistakes, but the public understandably expects judges to avoid s ystematic errors. This expectation however, might be unrealistic. Psycholog ists who study human judgment and choice have learned that people frequentl y fall prey to cognitive illusions that produce systematic errors in judgme nt. Even though judges are experienced, well-trained, and highly motivated decision makers, they might be vulnerable to cognitive illusions. We report the results of an empirical study designed to determine whether five commo n cognitive illusions (anchoring, framing, hindsight bids, the representati veness heuristic, and egocentric biases) would influence the decision-makin g processes of a sample of 167 federal magistrate judges. Although the judg es in our study appeared somewhat less susceptible to two of these illusion s (framing effects and the representativeness heuristic) than lay decision makers, we found that each of the five illusions we tested had a significan t impact on judicial decision making. Judges, it seems, are human. Like the rest of us, their judgment is affected by cognitive illusions that can pro duce systematic errors in judgment.