Unions have to disclose just about everything they spend money on to the Department of Labor, and the Wall Street Journal uses that information. It's a blunt tool, though, that includes, as reporters Tom McGinty and Brody Mullins note, "bratwursts to feed Wisconsin workers protesting at the state capitol last year" as well as direct contributions to candidates. More significantly than bratwursts, every dollar unions spent campaigning for the Affordable Care Act is counted in this analysis, as is money spent pushing to strengthen workplace safety protections and just about everything else unions do that could in any way influence policy at any level.
As the Wall Street Journal acknowledges, corporations don't face the same reporting requirements, so we simply cannot know how much they spend on equivalent activities:
Comparisons with corporate political spending aren't easy to make. Some corporate political spending, such as donations to the U.S. Chamber of Commerce's political wing, doesn't need to be disclosed. What does have to be disclosed can't be found in a single database or two, as is the case with unions.If you want to compare union and corporate political spending, then, a key question is whether there's any reason to believe that union political spending on things not included in the kinds of disclosure that businesses also must file is proportionally greater than business spending on those things. Because the disclosures that both businesses and unions file show that corporate interests spend a lot more than unions on lobbying as well as elections. So if business interests' undisclosed political expenditures are in the same proportion to the disclosed ones—as union political expenditures disclosed through Department of Labor filings are to ones businesses also disclose—then unions are still vastly outspent.
Now, there's an argument to be made, as Hamilton Nolan does make it, that, regardless of how their political spending stacks up to corporate spending, union resources should be shifted toward organizing more workers rather than politics. But that's why it's important to understand that much of the "political" spending included in this analysis is for things like preventing Ohio's anti-union Senate Bill 5 from becoming law, or preventing anti-union legislation, successfully or not, in states like New Hampshire and Indiana. In these cases, political spending is basically a precondition for organizing any workers. Unions are in a bitch of a double bind. If they don't spend on politics, Republicans are more likely to be elected who will pass any law they can think of to make union organizing illegal or impossible. But the more resources they spend on things other than organizing workers, the fewer workers they will organize.
That, however, is hardly the Wall Street Journal's concern. And the direct answer to the political attack on unions set up by the WSJ's reporting here is simply that this is a conversation we can have when businesses disclose anywhere near as much about their political and issues advocacy spending as unions do, and give shareholders as much input into those expenditures as union members have.