The Tax Collector’s Routes

A tax collector visited villages to audit their books. With twenty villages and time for only five audits per season, he had to choose wisely.

At first, he audited the five largest villages. The smaller villages, knowing they were safe, began underreporting. He switched to auditing randomly, but his choices still showed patterns — he avoided long journeys, audited clusters, returned to past cheaters.

Smuggling networks mapped his tendencies.

His superior told him: “Stop choosing. Draw lots. Weight them by village size, but let chance decide. If even you don’t know where you’ll go, no one can prepare for your arrival.”

Compliance improved immediately. The randomness was the enforcement.