"The business of Specialty Group is my family secret, a secret that will be kept -- as allowed by applicable law -- for at least another 50 years," Rose said in his statement.
FreedomWorks is among the most prominent organizations supporting the conservative tea party and was headed for years by former GOP House Majority Leader Dick Armey. Armey recently left the group in exchange for $8 million in payouts over 20 years from an outside benefactor, Richard J. Stephenson, according to a confidential agreement obtained by the AP. Stephenson is a prominent fundraiser and founder and chairman of the Cancer Treatment Centers of America.
The source of the money linked to Rose is unclear. Rose identified himself as Specialty Group's chief executive, president and general counsel, but there was no evidence that the company or Rose could afford to give away $12 million. County register records indicate a William S. Rose Jr. listed at one of Rose's former addresses owes $69,881 in federal back taxes, which a county official said Friday hasn't yet been settled. Property tax records show Rose's current home is appraised at $634,000.
Armey, in a previous interview with the AP, said he didn't know Rose and wasn't aware of where Specialty Group's donations may have originated.
The Supreme Court cleared the roles of super PACs in legal cases that included its landmark Citizens United ruling, which greatly expanded the limits and sources of money in politics. But even justices who supported increased giving -- which the court has equated with free speech -- said that citizens deserve to know who was behind money given to politicians.
"I think Thomas Jefferson would have said the more speech, the better," Justice Antonin Scalia said in July. "That's what the First Amendment is all about, so long as the people know where the speech is coming from."
Determining who is behind the money hasn't always been easy to determine.
One company dissolved In summer 2011 shortly after giving $1 million to a super PAC supporting Romney. It turned out to have been formed by Ed Conard, a Romney supporter who once worked with the former Massachusetts governor at the private equity firm Bain Capital.
Months later, a $400,000 gift from a limited liability partnership was traced to a fund connected with Boston-based Hellman Jordan Management. The firm eventually acknowledged that a married couple who had raised money for Romney had received the $400,000 as part of an unspecified investment disbursement and instructed Hellman Jordan to give it the super PAC supporting Romney.
"This is the huge issue," said Rep. Chris Van Hollen, D-Md., who is well known in Congress for trying to expand campaign-finance disclosure laws. "Transparency leads to more accountability, and the voters have the right to know who is spending gobs of money to influence their vote."