Republican senators angling to get President Trump’s Big Beautiful Bill over the line may come to regret their decision to use budget gimmicks to do it when Democrats retake the Senate majority, whether it be next year or further down the line. For the first time in history, Republicans voted on Monday to use a new process to get around certain Senate rules and make the president’s 2017 tax cuts permanent. 

On Monday morning, the Senate voted along party lines — 53 to 47 — to use what is known as a “current policy baseline” to calculate the total cost of the president’s One Big Beautiful Bill. That means that by the Republican reckoning, extending the 2017 tax cuts, which were originally meant to be temporary, will cost zero dollars instead of trillions of dollars when it comes time to tally up the price tag for Mr. Trump’s signature legislation. 

By using such an accounting trick, Republicans are opening the door for Democrats to get around Senate rules in the future in order to enact their own pricey policy items, including, possibly, Medicare for All or expensive new tax credits for green energy or any number of Democratic pet projects. 

Democrats are raging against the GOP budget gimmick, saying that Republicans are forever changing the Senate’s legislative process. 

“I’ve been here a long time. Not only have I been the Budget [Committee] chair, I am the longest-serving Democrat on that committee, and in my 33 years here in the United States Senate, things have never — never — worked this way,” Senator Murray, the top Democrat on the Appropriations Committee, said on the Senate floor on Sunday. She is also the longest-serving Democrat in the Senate. 

“We have never seen anything like this — not in my time here in the Senate, not in my time on this planet,” Ms. Murray said. “You are trashing the rules in order to pass this egregious bill.”

Democrats have already hinted that they could use this same gimmick to advance their own priorities in the future. In February, when Republicans began kicking around the idea of using the current policy baseline to advance their own agenda, a group of Senate Democrats asked an administrative House committee if they could — hypothetically — use the trick to make other policy objectives permanent. 

Senators Warren, Bennett, Welch, Cortez-Masto, and Warner wrote at the time to the Joint Committee on Taxation to ask if things like the child tax credit or the Affordable Care Act’s tax credits could be “cost-free” by simply using that policy baseline. Now, the GOP has turned that hypothetical into reality with this latest gimmick. 

The reason Republican senators are doing this is because they want to get around certain Senate restrictions on what can be changed in the federal budget. Earlier this year, Congress passed a budget blueprint for the budget process currently playing out on the floor of the Senate that set both floors and limits on what committees could spend or cut. 

That blueprint called for between $4 trillion and $4.5 trillion in tax cuts, but only if they are accompanied by a certain amount of spending cuts. The more spending they cut, the more taxes they could cut, the blueprint stated. By zeroing out the cost of trillions of dollars being used to make temporary cuts permanent, the Senate GOP is suggesting that their tax reforms cost American taxpayers nothing. 

The Committee for a Responsible Federal Budget — a nonpartisan watchdog group that analyzes federal spending — says the gimmick used by Republicans is in clear violation of Congress’s budget agreement. It says that the Senate version of the bill delivers nearly $4.5 trillion in tax cuts accompanied by only $1.4 trillion in spending cuts — well outside the budget blueprint’s limit for the spending cuts to tax cuts ratio, according to its analysis. 

“As currently written, the Senate bill would borrow hundreds of billions of dollars more than allowed under the House reconciliation instructions. The Senate should not pass such a massive amount of borrowing, and the House should not consider such an egregious violation of its rules,” the think tank wrote in its analysis.