Molly Riley/Reuters

Democrats on the verge of losing their majority in the Senate can take some solace: At least they'll still have the filibuster that Republicans used against them so aggressively the last four years.

The Supreme Court on Monday rejected an appeal from the good government group Common Cause that challenged the constitutionality of the longstanding Senate rule that effectively created a 60-vote, or three-fifths, threshold for most legislation.

The case, which was always a long shot for the plaintiffs, featured a couple of oddities. Along with Common Cause and three immigrants, it was brought by a quartet of House Democrats who argued that their votes on campaign finance and immigration legislation were nullified by Republicans who blocked the bills from receiving an up-or-down vote on the Senate floor. The lead defendant on the challenge, however, was another Democrat, Vice President Joe Biden, in his official capacity as president of the Senate. And while the target was conservative Republicans whom Democrats have labeled as obstructionists, the fact that the legal process dragged on for nearly two years means that it could be Democrats who soon benefit from the court's decision to reject the appeal.

The filibuster has faced challenges before, but courts have generally thrown them out because the individuals or groups bringing the cases did not have the legal standing to do so. "What made this different is we had four members of Congress," said Stephen Spaulding, the policy counsel for Common Cause, in reference to Representatives John Lewis, Michael Michaud, Hank Johnson, and Keith Ellison.

The Constitution gives the House and the Senate the power to write their own rules, and Senate Democrats earlier this year acted on their own to effectively eliminate the minority's ability to filibuster nominations. But, citing the Federalist Papers, the lawmakers and Common Cause argued that the Framers never intended that a three-fifths supermajority was necessary for any Senate action to move forward, Spaulding said. The Constitution details specific instances where a supermajority is needed, such as impeaching the president or approving treaties. Common Cause argued that these were the exclusive actions that required more than a simple majority and that the Senate could not just raise the bar for any legislation or nomination in the same way as it could, say, bar certain members from voting.

The challenge presented an awkward situation for the Senate officers named as plaintiffs, and Biden in particular, since it involved legislation in the Disclose Act and the Dream Act that he had enthusiastically supported. And while Biden served for 36 years in the Senate, he, too, had complained about the GOP's nearly endless use of the filibuster to block or delay legislation and nominations. Rather than defend the filibuster on the merits, lawyers for the Senate countered that Common Cause and the lawmakers did not have standing to bring the case, citing the previous failed challenges to the filibuster. It also agreed with a district court ruling that the question was a political in nature and not a matter for the courts to decide.

The D.C. Circuit Court of Appeals also ruled against Common Cause, and on Monday the Supreme Court issued its own rejection of the case without comment. “The Supreme Court’s refusal to hear Common Cause’s case challenging the constitutionality of the U.S. Senate’s filibuster rule is both shortsighted and ominous,” the group's president, Miles Rapoport, said in a statement. “Instead of protecting debate, the 60-vote filibuster rule has shut down discussion on important legislation, from a living wage to addressing climate change."

It's an argument Democrats have been making for years, but it will be interesting to hear what they have to say if they find themselves in the Senate minority come January. If they want to stop conservative legislation gutting Obamacare, cutting spending, or scrapping environmental regulations from advancing to a vote, they'll now have the Supreme Court to thank. That is, unless the Republicans in power change the rules.

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