Of course, as always this is just the tip of the iceberg on fraudulent returns.

FORBES: Guest Post: Choosing Where Taxes Go

He also has cautioned those who believe they have filed fraudulent returns to pay the government what they owe in taxes.

FORBES: The Taxman Sueth

For example, in Greeley, Colorado this year, district attorney Buck Young raided a tax filing agency to find over 1, 000 fraudulent returns by unlawful workers.

FORBES: Guest Post: Choosing Where Taxes Go

In one survey, more than half of respondents asserted that the IRS was solely accountable for ensuring that fraudulent returns could not be successfully filed.

ENGADGET: Editorial: Countering ID theft requires better awareness campaigns

Current federal law prevents the IRS from turning over the very evidence of the crime the fraudulent returns that state and local prosecutors need to bring the scammers to justice.

WSJ: Cyrus Vance Jr.: Why Your Tax Return Isn't Safe

The police say they run across street corner drug dealers and robbers who have been in and out of prison for years now making lots of money by filing fraudulent returns.

FORBES: Billions in Tax Refund Fraud--and How to Stop Most of it

And Kelvin Crucey, who owned a tax-preparation business in New York, in February of 2011 was sentenced to 27 months in prison for preparing fraudulent returns based on stolen Puerto Rican identities.

WSJ: Billions Lost in Tax-Refund Scam

In September, five men were sentenced to between 40 and 98 months in prison for cashing checks tied to fraudulent Puerto Rican tax returns.

WSJ: Billions Lost in Tax-Refund Scam

In my opinion, the spectacular returns many funds quote are fraudulent-if not outright, then by omission.

FORBES: Pensions Funds: Funding Unsavory Practices of Venture Capitalists (May 1, 2000)

So did MPI, a quantitative-research firm, after an analysis in 2006 failed to find a legitimate strategy that matched his returns though they were closely correlated with those of Bayou, a fraudulent hedge fund that had collapsed a year earlier.

ECONOMIST: The Madoff affair