“There will be a terrible problem and then the question becomes will the federal government help,” Buffett, 79, said today at a hearing of the U.S. Financial Crisis Inquiry Commission in New York. “I don’t know how I would rate them myself. It’s a bet on how the federal government will act over time.”

Berkshire’s investment portfolio included municipal bonds valued at less than $3.9 billion as of March 31, down from more than $4.7 billion at the end of 2008. The company had a maximum of $16 billion at risk in derivatives tied to such debt, according to the company’s annual report for 2009.
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Buffett said last month that the U.S. may feel compelled to rescue a state facing default after the government committed $700 billion to bail out financial firms and automakers. “It would be hard in the end for the federal government to turn away a state having extreme financial difficulty when they’ve gone to General Motors and other entities and saved them,”
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About $14.5 billion of municipal bonds defaulted in 2008 and 2009… Many those were securities backed by revenue from nursing homes, property developments and other projects without claim to government tax revenue.
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Defaults by local governments with the power to raise taxes are less common. Jefferson County, Alabama, defaulted on more than $3 billion of bonds backed by sewer fees after the deals grew more costly in the wake of the credit crisis in 2008. Vallejo, California, filed for bankruptcy in 2008 after its tax revenue tumbled.