Why Won't Campbell Brown Reveal The Donor List To Her Education Reform Advocacy Group?

From David Callahan at Inside Philanthropy:

When queried by a reporter for Politico, Brown declined to name the donors to the advocacy group she's started, the Partnership for Educational Justice, except to say that they come from both political parties.

Carl Korn, a spokesperson for New York State United Teachers, told Politico that PEJ was an "astroturf" group funded by right-wing “extremists," and added that "Campbell Brown ought to disclose her donors who are funding this attack on working people and the rights of teachers... We will vigorously defend due process and seniority rights against these attacks by billionaire hedge fund managers.”

It could literally be years before we know where PEJ's money is coming from. Or perhaps never, given that nonprofits don't have to disclose their funders and there's also no requirement for individuals to publicly disclose where they donate funds, assuming they don't channel those gifts through a foundation.

In all likelihood, though, the donors behind PEJ—which, by the way, has only four staff, including Brown, and has recruited a pro bono legal team—are the usual suspects. It will be the same donors who give money to pro-charter and ed reform groups, particularly those with a big presence in New York: Teach for America, Achievement First, the New Teacher Project, and so on. (Reshma Singh, the executive director of PEJ, previously worked for both Teach for America and Achievement First.) 

What's Brown hiding that she refuses to reveal the donor list?