Following up on my previous post, NY Times: NY AG Investigates Tax Treatment of Bain Capital Management Fees:  Wall Street Journal, Informer Sparked New York Probe Attorney General Is Looking at How Buyout Firms Handled Management Fees, Tax Implications:

New York state Attorney General Eric Schneiderman's probe of tax
practices at private-equity firms is based on information from a
whistleblower, according to a person familiar with the matter.

The information came from someone who approached Mr. Schneiderman's
office between roughly nine months and a year ago, this person said.
Under the state's False Claims Act, the attorney general can investigate
alleged fraud against the state based on a whistleblower's allegations.

The ongoing probe is examining whether partners at private-equity
firms changed management fees into investment income to delay tax
payment and pay less—or avoid taxes altogether. Some private-equity
firms use so-called management-fee conversions, while other firms avoid
them.

If Mr. Schneiderman files a lawsuit and wins, defendants could be
liable for damages of as much as three times the taxes owed. It isn't
clear when he will decide whether or not to proceed with a lawsuit.

At least two other whistleblower claims related to management-fee
conversions have been filed with the Internal Revenue Service, which has
the authority to pay whistleblowers up to 30% of proceeds collected in
large cases. Such whistleblower cases usually take four to seven years
to resolve.