One of the report’s recommendations was that governments start disclosing the amounts promised to retirees, “so that everyone can see them.”

Government officials are in many cases loath to do that because they believe it will harm their credit ratings, driving up borrowing costs. And the unions that represent public workers believe calls for full disclosure mask a broad anti-labor campaign to cut benefits.

The disclosure issue has grown increasingly contentious in Washington. Republican members of Congress are planning to introduce a bill in the next few days that would require states and local governments to measure their pension obligations using the method now universally used to price municipal bonds. States and cities currently report their pension obligations as calculated by actuaries, and actuarial numbers can greatly distort economic reality.

It was actuarial numbers in Detroit, for instance, that obscured the value of that city’s pension promises before the bankruptcy.

States have long argued that as constitutional sovereigns, they cannot be forced to meet any federal pension disclosure requirements. Republican lawmakers are generally sympathetic to states’ rights issues, but they are also worried about being asked to bail out troubled pension systems in places like Illinois and Puerto Rico.

Since the tax-exempt treatment of municipal bonds is, in fact, a federal subsidy, they have written the bill to require full, market-based pension disclosure only in connection with tax-exempt borrowing. If states and cities remain unwilling to reveal their pension obligations, they could still borrow — but they could not market their bonds as tax-exempt.

Senate Republicans introduced a similar disclosure measure late last year as part of a package to help Puerto Rico through a huge debt crisis. The island appears not to have nearly enough money to pay both its bond debt and its retirees’ pensions, but up-to-date information about its pension system does not exist in the public domain.