Republicans stalled progress in the Senate on a House bill that would create a commission to study the January 6 Capitol riot, leading to renewed calls by Democrats to end the filibuster and eliminate the need for bipartisanship.

All but six GOP senators voted against cloture on Friday, keeping the House bill from getting the 60 votes it needed to end floor debate and elude a filibuster. The legislation calls for creation of a 10-member commission, much like the one that studied the September 11, 2001, terrorist attacks, to investigate the Capitol riot.

The proposed commission would enable Democrats to keep the party’s narrative of a GOP-inspired Capitol insurrection alive well into the 2022 election cycle. While such senators as Susan Collins (R-Maine) and Mitt Romney (R-Utah) have joined Democrats in calling for an independent probe, Senate Minority Leader Mitch McConnell (R-Kentucky) has argued that with congressional committees and the Justice Department already investigating the riot, a new commission would be redundant.

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Democrats control the executive branch and both houses of Congress, but they lack a supermajority in the Senate, meaning the opposition party can stand in the way of partisan legislation. With Republicans deploying their filibuster power for the first time since Democrats took control of the Senate in January, some lawmakers are calling for changing the rules to give themselves de facto one-party rule.

“If Senate Republicans can block an independent commission investigating a deadly armed attack on the Capitol because it might hurt their poll numbers with insurrectionists, then something is badly wrong with the Senate,” Senator Elizabeth Warren (D-Massachusetts) said after Friday’s cloture vote. “We must get rid of the filibuster to protect our democracy.”

Unlike the House, the Senate requires a three-fifths majority (60 votes) to end debate on a bill. The filibuster has been used since the 1830s, with senators debating continually – or threatening to do so – to block a bill from advancing to a vote, thereby giving the minority party some leverage in legislative negotiations.

Senate rules were revised in 1917 to allow for a cloture vote to end debate, then requiring a two-thirds majority. The cloture threshold was lowered to a three-fifths majority in 1975.

US Capitol riot probe blocked as Senate Republicans use FILIBUSTER to stall action on bill creating 9/11-style commissionRT

President Joe Biden has shown reluctance to support eliminating the filibuster, a key feature of the American political system, but he signaled openness to changing the rules in March.