The financial crisis is a vivid reminder that there can be many risks to financial stability, and of the need for strong internal and external constraints on banks. Here, the “three pillars” of regulation, supervision, and bank culture must all play effective roles. Regulation establishes what is legally permissible for banks to do; supervision helps to reinforce those rules and evaluate whether the bank’s controls and other processes are conducive to safety and soundness; and bank culture sets the norms for what is appropriate behavior. 9 But, at the same time, these pillars are mutually reinforcing. Regulation and supervision, for example, attempt to address various market failures in banking that can contribute to excessive risk taking.10 Bank culture, in turn, helps establish norms in areas where regulation may be silent. In this way, regulation, supervision, and bank culture are complements, and deficiencies in any of these pillars can be problematic. For example, as we have seen in cases of unsafe or unethical behavior in recent years, strong regulation and supervision cannot substitute for deficiencies in bank culture—especially not on a timely basis. It is the public sector’s job to establish and enforce rules, but rules are inherently limited in their ability to constrain conduct and behavior. Much of our regulatory regime has been developed in response to financial problems that have arisen over time. Because regulation is typically reactive in this way, it may not always keep pace with the evolution of the financial system or the broader economic environment.

I think these goals are broadly shared by supervisors and banks alike, which suggests to me that the relationship between supervisors and banks does not always need to be adversarial. Indeed, a healthy dialogue helps this supervisory process to work well. For example, it is important that firms are proactive in revealing problems to their supervisors. And, individual institutions can certainly benefit from the horizontal perspective that supervisors bring to examinations. This perspective can highlight where the firm stands vis-à-vis best practices, or where there may be important vulnerabilities in its operations. Of course, there is an irreducible amount of tension built into this relationship, given that each party’s roles, interests, and responsibilities will not always coincide. Banks are naturally more sensitive to constraints on their profit opportunities or dividend policies and to the costs of regulation. They may also question how much protection is necessary—for example, how stringent the capital requirements or how severe stress testing assumptions should be. These are areas where I would expect perspectives to differ. Supervisors are principally focused on compliance with laws and regulations as well as issues of safety and soundness. They also bring to their work a perspective on financial stability that may not match the more narrow interests of the firm. For example, supervisors seek to address the externalities created by the failure of a systemically important firm by imposing higher capital and other requirements than the firm would likely select if left to its own devices.