A federal crackdown is proceeding quietly against bankers accused of systematically defrauding states, local governments and non-profits.
Since 2009, federal authorities have secured 19 convictions or guilty pleas as part of the investigation, including seven since April. The cases have put a spotlight on the municipal bond market, an esoteric corner of the finance world where prosecutors say Wall Street firms have repeatedly used inside information to pad their bottom lines at the public's expense.
"[T]hese complex, seemingly uninteresting backroom deals have a real impact on taxpayers," Richard Weber, head of the Internal Revenue Service's criminal division, said following the convictions of three former UBS (UBS) bankers last month.
Those implicated over the course of the investigation have come from firms including Bank of America (BAC, Fortune 500), JPMorgan (JPM, Fortune 500) and General Electric (GE, Fortune 500). Government agencies have collected more than $740 million in penalties, restitution and other fees from the institutions involved.
The probe targets bankers who have colluded about the offers they've made as they bid on contracts to invest municipal bond proceeds.
How the market works: State and local governments issue municipal bonds to fund things like road construction and school repairs. In some cases, they issue the bonds on behalf of non-profits or companies that will spend the money on projects benefiting the public.
The market for these bonds is massive, with more than $3.7 trillion outstanding as of the beginning of this year, according to the Securities and Exchange Commission.
Governments and other issuers don't typically spend all the proceeds from their bonds right away, instead investing some of the money and holding it for future expenditures.
To figure out how to invest that money, they hire brokers who advise on and manage a bidding process among financial institutions competing for their business. Bids are solicited from firms like UBS and JPMorgan, which submit the interest rates they're willing to offer on the bond proceeds.
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