June 29 (Bloomberg) -- The Bank for International Settlements, which acts as a bank for the world’s central banks, should know fudged numbers when it sees them. What may come as a surprise is how openly it has been discussing the problem of bogus balance sheets at large financial companies.

“The financial sector needs to recognize losses and recapitalize,” the Basel, Switzerland-based institution said in its latest annual report, released this week. “As we have urged in previous reports, banks must adjust balance sheets to accurately reflect the value of assets.” The implication is that many banks are showing inaccurate numbers now.

Unfortunately the BIS’s suggested approach is almost all carrot and no stick. “The challenge is to provide incentives for banks and other credit suppliers to recognize losses fully and write down debt,” the report said. “Supporting this process may well call for the use of public sector balance sheets.”

So there you have it. More than four years after the financial crisis began, it’s so widely accepted that many of the world’s banks are burying losses and overstating their asset values, even the Bank for International Settlements is saying so -- in writing. (The BIS’s board includes Federal Reserve Chairman Ben Bernanke and Mario Draghi, president of the European Central Bank.) It fully expects taxpayers to pick up the tab should the need arise, too.

No Change

In this respect, little has changed since the near-meltdown of 2008, especially in Europe. Spain has requested 100 billion euros ($125 billion) to rescue its ailing banks. Italy, perhaps the next in line for a European Union bailout, is weighing plans to boost capital at some of the country’s lenders through sales of their bonds to the government.

Those bank rescues almost certainly won’t be the last. All but four of the 28 companies in the Euro Stoxx Banks Index trade for less than half of their common shareholder equity, which tells you investors don’t believe the companies’ asset values. While it may be true that the accounting standards are weak, the bigger problem is they are often not followed or enforced.

Government bailouts might be easier for the world’s taxpayers to swallow if banks were required to be truthful about their finances, as part of their standard operating procedure. Nowhere in its report did the BIS discuss the role of law enforcement, although the last time I checked it’s against the law in most developed countries to knowingly publish false financial statements. There have been few fraud prosecutions against executives from large financial institutions in recent years, in the U.S. or elsewhere, much to citizens’ outrage.

In the BIS’s eyes, it seems that it’s enough to merely encourage or incentivize banks to come clean about their losses, by dangling the prospect of additional taxpayer support before them. For example, on the subject of how to deal with overvalued mortgage loans: “One frequently used option is to set up an asset management company to buy up loans at attractive prices, i.e., slightly above current market valuations,” the BIS report said. “Alternatively, authorities can subsidize lenders or guarantee the restructured debt when lenders renegotiate loans.”

The BIS report got this much right: The lack of transparency and credibility in banks’ balance sheets fuels a vicious cycle. When investors can’t trust the books, lenders can’t raise capital and may have to fall back on their home countries’ governments for help. This further pressures sovereign finances, which in turn weakens the banks even more. The contagion spreads across borders. There is no clear end in sight.

Propping Up

To date, the task of propping up the economies in Europe and the U.S. has fallen largely to central banks. As the BIS wrote, easy-money policies also can make balance-sheet repairs harder to accomplish.

“Prolonged unusually accommodative monetary conditions mask underlying balance sheet problems and reduce incentives to address them head-on,” the report said. “Similarly, large-scale asset purchases and unconditional liquidity support together with very low interest rates can undermine the perceived need to deal with banks’ impaired assets.”

At some point, the cycle will break, only nobody knows when. This you can count on: It will take more than subtle inducements to make banks fess up to all their losses. Prosecutors must have a role. There’s nothing like the threat of a courtroom trial to focus a bank executive’s mind. The risk just has to be real.

(Jonathan Weil is a Bloomberg View columnist. The opinions expressed are his own.)

Read more opinion online from Bloomberg View. Subscribe to receive a daily e-mail highlighting new View editorials, columns and op-ed articles.

Today’s highlights: the editors on why John Roberts saved Obamacare and why Mexico’s next president must combat its economic cartels; Stephen L. Carter in praise of Supreme Court secrecy; Noah Feldman on Roberts’s restraint; Ramesh Ponnuru on misunderstanding the court’s decision; Jeffrey Goldberg on whether women can have it all; William Pesek on Myanmar’s economic development; Steven Greenhut on using eminent domain to take over foreclosed homes.

To contact the writer of this article: Jonathan Weil in New York at jweil6@bloomberg.net.

To contact the editor responsible for this article: James Greiff at jgreiff@bloomberg.net