Following a 2011 complaint filed by watchdog groups that a loan received by the U.S. Chamber of Commerce was used for political and lobbying activities during the 2004 election cycle, the New York State Attorney General's Office has launched an investigation of the tax-exempt business organization, the New York Times reports.

On Tuesday, New York State attorney general Eric T. Schneiderman issued a subpoena to the National Chamber Foundation to determine whether it had channeled funds to the Chamber of Commerce to influence legislation and the 2004 presidential and congressional elections. Schneidermann also announced that his office was reviewing connections between NCF and the New York City-based Starr Foundation, which made significant contributions to NCF in the years leading up to the 2004 elections. During that period, the chamber received an $18 million loan from NCF, ostensibly for a capital campaign. But according to watchdog groups, including U.S. Chamber Watch, the loan was used for lobbying activities and political advertising, mostly against Democratic candidates.

The Chamber of Commerce is one of the biggest tax-exempt groups headquartered in Washington, D.C., and much of its funding is provided by corporations. In 2011, the chamber spent $66 million on lobbying activities, and according to chamber officials it is set to spend at least $50 million during this year's election cycle.

The Starr Foundation was established by insurance entrepreneur Cornelius Vander Starr and is led by former AIG chairman Maurice "Hank" Greenberg, who has served on the board of the Chamber of Commerce. Although NCF has not confirmed whether the grants from the foundation were made to cover the loan to the chamber, an examination of its tax returns by the Times suggest that the grant funds made the loan possible.