WASHINGTON – One of the greatest privileges I experienced during my years working on Capitol Hill was the chance to enter the Senate chamber – the sanctum sanctorum of our democracy – while the Senate was in session. So, to watch a mob desecrate that sacred space Jan. 6 – hanging from walls, rifling through desks and taking selfies in the presiding officer’s chair – was deeply disturbing.

The rioters did violence to a hallowed institution. But today it is Democrats who are proposing to do violence to the institution by eliminating one of its most fundamental tenets: the right of the minority to delay, amend or block legislation. And unlike the damage done by the mob, the damage Democrats propose would be irreparable.

The “abolish the filibuster” movement among Democrats has been set back only thanks to the opposition from two senators, Joe Manchin III, D-W.Va., and Kyrsten Sinema, D-Ariz. But those who want to bypass the minority have found a workaround. They’re considering eliminating the Byrd rule – an arcane but vitally important pillar of Senate procedure that prevents extraneous provisions from being tacked onto must-pass budget reconciliation legislation that requires only a simple majority vote to pass.

On Tuesday, the Senate’s Democratic majority voted to move forward on President Joe Biden’s $1.9 trillion COVID-19 relief plan using the reconciliation process, which would allow them to pass it without any GOP votes. Their COVID plan includes provisions, such as a $15 minimum wage, that violate the Byrd rule. As Martin B. Gold, former counsel to two Senate majority leaders, explained to me, a provision is extraneous under the Byrd rule if it doesn’t affect the federal budget, or if the fiscal impact is merely incidental to the broad policy effects of the provision. A minimum-wage increase does not meet that test because its primary impact is on the private market. “You cannot have a fiscal tail wag a nonfiscal dog,” he said.

This means that if Democrats tried to pass the minimum wage as part of the budget reconciliation process, the Senate parliamentarian would advise the presiding officer that a minimum-wage increase is out of order. There are two ways Democrats could overcome that obstacle. First, they could use a blunt instrument and invoke the “nuclear option” to eliminate the Byrd rule altogether. But they’d need 50 votes to do that, and Manchin and Sinema may balk. This is especially true since the Byrd rule is named for Sen. Robert C. Byrd of West Virginia, whom Manchin counts as mentor. In an interview with Fox News’ Bret Baier, Manchin said he would vote to protect the Byrd rule and “defend the legacy of Robert C. Byrd.”

But there is another way around the Byrd rule that Manchin cannot so easily block. Vice President Kamala Harris, serving as presiding officer of the Senate, could simply ignore the Senate parliamentarian and rule that a minimum-wage increase does not violate the Byrd rule. Republicans would then have to muster 60 votes to overrule her. That means even if both Manchin and Sinema voted with Republicans, they could not stop Harris. Their only option would be to vote against the entire reconciliation bill, killing their party’s entire COVID relief package.

Since the Senate works on precedent, once the presiding officer ignores the parliamentarian’s ruling, the Byrd rule will have been gutted. From that point forward, the majority party can insert anything it wants into a reconciliation bill using the same precedent, effectively eliminating the filibuster. Why would any Senate majority leader break his neck to get 60 votes for a bill if he could just use budget reconciliation to pass it with 51 votes? Democrats will be able to pass anything – an increased minimum wage, District of Columbia statehood, court-packing, the Green New Deal, single-payer health care – by simple majority.

There have been five COVID relief bills passed in the past year, all using regular order. So, why would Democrats use reconciliation now – especially when 10 Republicans have offered them a path to a filibuster-proof bipartisan majority? Because they don’t want to make any significant policy concessions to the minority to get those 10 Republican votes. And in service of that, they are willing to destroy an institutional guardrail that has kept our country centrist and stable.

Manchin can save the guardrail his mentor created by warning Senate Majority Leader Chuck Schumer, D-N.Y., that he will kill the whole relief package if Democrats ditch the Byrd rule – and then doing so if they don’t listen. Manchin has said he will vote only “in a bipartisan way.” Now he has to follow through. It’s not just the legacy of Robert C. Byrd, but the fate of the U.S. Senate as the world’s greatest deliberative body, that rests in Manchin’s hands.