The new rules governing the House of Representatives, the product of a deal between Speaker McCarthy and the Republicans who opposed his election, could spur chaos in the new Congress and create gridlock as members navigate legislative requirements in a newly unstable environment.

The rules package, adopted with only fleeting resistance from a couple of Republicans, reportedly includes a secret three-page addendum that some congressional Republicans won’t even acknowledge. Punchbowl News first reported on the addendum’s existence, and Representative Ken Calvert later appeared to confirm it to Axios. Others, however, have been reluctant to talk about it.

The addendum reportedly contains concessions Mr. McCarthy made during the battle for his election, including a freeze of federal spending at 2022 levels and three seats on the rules committee for Freedom Caucus members.

“There is a secret three-page addendum to the House Rules that secured the support of the wackiest members of the House and the American public deserves to know what’s in it,” Senator Schatz, a Democrat, said of the addendum.

The specifics of both the addendum and the deal with the GOP holdouts are not public. What is clear, however, is that representatives will be entering a Congress operating under dramatically different rules than the previous House.

According to what is known of the new rules package, a bill may not be introduced unless that bill’s sponsor submits a “statement setting forth the single subject of the bill or joint resolution,” effectively outlawing bills tackling multiple topics.

This would eliminate legislation like the omnibus spending bill that passed in late December, and will push more debate on specific topics onto the floor of the House.  In previous Congresses, representatives mostly just voted yes or no on legislation.

Alongside a change empowering legislators to call the germaneness of an amendment into question, this rule reset also will theoretically cut down on unrelated earmarks added to large bills.

Another high-profile rules change will require members of Congress to be given a copy of a bill they will be voting on 72 hours in advance of the vote.

The previous rule only required leadership to supply members with a bill the day before the vote. Legislation will now theoretically be shorter than before, and proponents of this change say it will give legislators time to actually read bills before voting on them.

The new rules also include a litany of provisions aimed squarely at the budget, including a statement saying that the new Congress will completely ignore a resolution from the last Congress that establishes a budget estimate for the next decade.

Chief among these changes is a new rule requiring bills to have a net neutral or negative effect on the budget, meaning that bills may not increase government spending. In effect, this policy, known as Cut as You Go, requires legislators to cut programs or find efficiencies in the national budget for each new dollar of spending they aim to pass.

The rule is a departure from the previous Pay as You Go policy, which took a similar incremental approach to balancing the budget but also allowed legislators to fund new legislation through new taxes or tax increases.

Representatives also will be required to estimate the budgetary effects of any changes of “economic output, employment, capital stock, and other macroeconomic variables” resulting from proposed legislation.

The House will now need the support of three-fifths of the body to raise or create new taxes, meaning tax increases of any sort are unlikely to pass in the next two years.

This new threshold, however, does not apply to tax cuts. Because most of the new budgetary restrictions are aimed specifically at increases in spending, the House could still drive up the national deficit via tax cuts relatively easily.

The new Congress has already provided an example of this phenomenon in its recent vote to cut funding given to the IRS by the last Congress.

The bill, which was not subject to the 72-hour waiting period that goes into effect in February, would cut IRS funding by $71.5 billion while simultaneously decreasing revenue by $186 billion, according to the Congressional Budget Office.

If the measure were passed in the Senate and signed by President Biden, which is unlikely, it would lead to a net increase in the federal deficit of more than $114 billion.

Representatives will be navigating these new rules against the backdrop of a one-member motion to vacate, which could spur another battle for the speakership if a majority vote to oust Mr. McCarthy. This would require only six Republicans to join the chamber’s 212 Democrats.