The structure of the auditing business appears problematic: Typically, major companies pay auditors to examine their books under the so-called “third-party” audit system. But when an auditing firm’s revenues come directly from its clients, the auditors have an incentive not to deliver bad news to them.

So: Does this arrangement affect the actual performance of auditors?

In an eye-opening experiment involving roughly 500 industrial plants in the state of Gujarat, in western India, changing the auditing system has indeed produced dramatically different outcomes — reducing pollution, and more generally calling into question the whole practice of letting firms pay the auditors who scrutinize them.