Much discussion of corporate governance in the last few years has centered on reforms advocated by ISS and CII and indices of good corporate governance practice created and maintained by such groups. A new study by Roberta Romano, Sanjai Baghat, and Brian J. Bolton, however, concludes that there is “no consistent relation between governance indices and measures of corporate performance.” The authors continue,
[T]here is no one “best” measure of corporate governance: the most effective governance institution appears to depend on context, and on firms’ specific circumstances. It would therefore be difficult for an index, or any one variable, to capture critical nuances for making informed decisions. As a consequence, we conclude that governance indices are highly imperfect instruments for determining how to vote corporate proxies, let alone for portfolio investment decisions, and that investors and policymakers should exercise caution in attempting to draw inferences regarding a firm’s quality or future stock market performance from its ranking on any particular corporate governance measure. Most important, the implication of our analysis is that corporate governance is an area where a regulatory regime of ample flexible variation across firms that eschews governance mandates is particularly desirable, because there is considerable variation in the relation between the indices and measures of corporate performance.
The paper is entitled The Promise and Peril of Corporate Governance Indices and the full text is available on SSRN.