To reveal, but not to regulate
Standard-setters should defuse the argument by making clear that their job is not to regulate banks but to force them to reveal information. The banks, their capital-adequacy regulators and politicians seem to dream of a single, grown-up version of the truth, which enhances financial stability. Investors and accountants, however, think all valuations are subjective, doubt managers' motives and judge that market prices are the least-bad option. They are right. A bank's solvency is a matter of judgment for its regulators and for investors, not whatever a piece of paper signed by its auditors says it is. Accounts can inform that decision, but not make it。
Banks' regulators have to take responsibility. If they want to remove the mechanical link between drops in market prices and capital shortfalls at banks, they should take the accounts that standard-setters create for investors and adjust them when they calculate capital. They already do this to some degree. But the banks' campaign to change the rules is making inevitable a split between two sets of accounts, one for regulators and another for investors. The FASB and IASB can help regulators to create whatever balance-sheet they want. But in doing so they must not compromise their duty to investors。