There are also whistleblower laws now that provide similar incentives for identifying large-scale tax and securities frauds.

FORBES: Celebrating The 150th Birthday Of 'Lincoln's Law': Privatized Fraud Fighting

The U.S. Supreme Court decided two securities-law cases today, handing a victory to plaintiff lawyers in one and narrowing the time frame for the Securities and Exchange Commission to go after frauds in the other.

FORBES: Supreme Court Clips SEC's Wings In Gabelli Case; Defense Loses In Amgen

Last year the SEC and some state securities regulators warned that they have become vehicles for Ponzi schemes and other frauds.

WSJ: IRAs Get Sexier