Maurice Cunningham is a professor of political science at the University of Massachusetts who specializes in unmasking the influence of billionaires’ dark money. “Dark money” is money that is contributed with the expectation that the donors’ name will not be disclosed. I wrote about the role of Cunningham in exposing the dark money behind the 2016 effort to pass a referendum to expand the number of charter schools in Massachusetts; his exposes alerted voters to the vast sums spent by out-of-state billionaires like the Waltons and Michael Bloomberg to buy education policy in Massachusetts.

As he demonstrates in this article, the Waltons–who cumulatively are worth about $200 billion–are still funding pro-charter, anti-union groups in Massachusetts, still pushing their anti-public school agenda. The Waltons’ vehicle of choice is the “Massachusetts Parents United” group, which claims to be just a lot of concerned moms while collecting millions each year from the Waltons and other oligarchs.

The leader of the Walton-funded parent group is collecting, according to tax records, nearly $400,000 a year. Not a bad gig.

Cunningham reviews a story in Commonwealth Magazine that compares funding for Massachusetts Parents United with funding for the state’s teachers union.

But there are crucial differences, Cunningham writes:

Stories like this tend to equate spending on organizations like MPU with the unions. They’re not comparable. Union funding comes from members’ dues. The unions are democratically organized. My local voted out an incumbent last year, as have other teachers’ unions. MTA term limits its president (a good thing, as Barbara Madeloni was far tougher than her surrender-prone predecessor Paul Toner). There is no democracy to MPU. The Waltons are from Arkansas and probably couldn’t find Chicopee or Tewksbury on a map; never mind getting Alice Walton to pronounce Worcester or Gloucester. The Waltons just write checks and measure ROI–return on investment. MTA and Massachusetts Federation of Teachers members live here. Want to hold the Waltons accountable for the vast changes to Massachusetts education policy they seek through MPU? Good luck with that.

If you’ve gotten this far let me say a few words about why I care about this stuff. We simply do not have a functioning democracy when the vast wealth of a few oligarchs sets the policy agenda and gains influence by showering money on upbeat sounding fronts like Families for Excellent Schools and Massachusetts Parents United. Nor do we have a functioning democracy when the true power—the men and women behind the curtain—remain unknown to the public and uncovered by the media. In Dark Money, Jane Mayer talks about “weaponizing philanthropy.” In Just Giving, Rob Reich points out the “plutocratic bias” enjoyed by the foundations. (Hey, did I mention all these public policy altering contributions by oligarchs are a valuable tax deduction to them? Yes, you’re subsidizing them to change your state’s policy. Never give a sucker an even break). Huge investments in policy change and hidden money threaten rule by the people.

And that’s what MPU is—a tax deductible front for oligarchs weaponizing their philanthropy in a campaign to privatize public goods. The Waltons, Koch, and other oligarchs don’t want us to peek behind the curtain. It is our democratic obligation to tear that curtain down.