Democrats in Congress last week introduced White House-backed legislation that would indirectly reinstate free-speech restrictions that the Supreme Court declared unconstitutional in January. Backers say the measure will force disclosure of corporate money in politics, but the real goal is to muzzle criticism—at least from some people.

The legislation, sponsored by Democrats Charles Schumer in the Senate and Chris Van Hollen in the House, would prevent government contractors and corporate beneficiaries of the Troubled Asset Relief Program from spending money on U.S. elections. It would also ban U.S. subsidiaries of foreign companies from making political contributions if a foreign national owns 20% or more of the voting shares in the company, or if foreign nationals comprise a majority of the board of directors.

The provisions are designed to undermine this year’s landmark Supreme Court Citizens United decision, which held that limits on independent campaign expenditures by corporations or unions violate First Amendment free speech guarantees. But, under the bill, unions with government contracts would not be subject to the same restrictions as corporations.

If, as proponents claim, their worry is that a company will use campaign contributions to win government contracts (pay-to-play), why does their bill not show equal concern that labor unions will support candidates with the goal of getting government contracts driven to union companies? The legislation also fails to impose limits on the foreign involvement of unions with global reach, such as the Service Employees International Union or the International Brotherhood of Electrical Workers.

It’s no coincidence that the lead authors of these bills are the current head of the Democratic Congressional Campaign Committee (Mr. Van Hollen) and the immediate past head of the Democratic Senatorial Campaign Committee (Mr. Schumer). And it’s no surprise that Republicans have been reluctant to sign on. The House bill has two GOP sponsors and the Senate bill has none.

When President Obama berated the High Court earlier this year for its free speech ruling, he was very specific about whose free speech he opposed. “This is a major victory for Big Oil, Wall Street banks, health insurance companies and other powerful interests,” said Mr. Obama of the decision, suggesting that despite the good governance rhetoric, this legislation is not about muzzling spenders generally so much as specific spenders who don’t always salute the Democratic agenda.