Schwab recommends dumping Chicago munis. But wait. Even safe-sounding revenue-backed debt, though on first sight not affected by pensions, may be affected by pensions. Schwab:

In Chicago, Moody’s downgraded sales tax revenue debt and motor fuel tax revenue debt based on the “lack of full legal segregation of pledged revenue from the general operations of the city” and its outstanding water and sewer debt based on the system’s “status as an enterprise of the city.