The rules and regulations governing dark-money groups are almost as mystifying as the names of their donors. In general, the Federal Election Commission requires groups that make electing candidates their "major purpose" to register as political committees, which means they have to disclose their donors.
But other groups can remain obscure simply by telling the FEC that their major purpose is not electing candidates—that they are, rather, "social welfare" nonprofits or trade associations. That means they have to identify only those donors who specifically earmark their money for political ads—something that rarely happens.
Under the tax code, these groups don't have to publicly report any of their donors' names. They are allowed to support candidates for office as long as promoting social welfare or industry is their primary purpose. But politics moves much faster than federal agencies, and by the time the Internal Revenue Service discovers that a group has crossed the line from nonprofit promotion to politicking, many operators have boarded up shop and moved on.
Take the liberal group Americans for Stable Quality Care. A rare coalition of pharmaceutical and health-care associations and unions, it spent more than $43 million in 2009 on ads promoting health care reform. After reform passed in 2010, the group changed its name to the Citizens for Strength and Security Action Fund and spent almost $3 million supporting liberal candidates for office in the midterms. After the 2010 elections, the group went dormant, and its website was taken down.