This article originally appeared on PolitiFact.
A fight between Republicans and Democrats could lead to an Oct. 1 federal government shutdown.
Democrats are trying to leverage the must-pass bill to extend Affordable Care Act subsidies; the Trump administration is tying a shutdown to potential mass federal worker layoffs.
READ MORE: What closes during a government shutdown? What we know about how it would unfold
The current battle focuses on expiring subsidies for the Affordable Care Act that Democrats say will hurt the ability of millions of enrollees to afford insurance. Democrats have also said they want to reverse Medicaid cuts that Trump signed into law this summer.
Republicans are seeking a bill to temporarily extend federal spending at current levels without any add-ons.
If the government shuts down, President Donald Trump and his administration — which has already defied norms on executive power — likely will seek to exert more power.
Trump's Office of Management and Budget under Russell Vought has moved with more executive authority over spending, which is typically left to Congress. The administration took steps to cancel foreign aid and asserted power to withhold billions of domestic spending.
"I would expect this shutdown to look different than any other shutdown," said Joshua Sewell, Taxpayers for Common Sense director of research and policy. He said he expects that the Trump team's actions would be guided by what they believe achieves the most for them politically.
Trump could use a shutdown to dismantle government functions, wrote Max Stier, chief executive of the Partnership for Public Service, a nonprofit focused on improving the federal government.
If lawmakers can't reach a deal, Stier wrote, Trump and Vought "will have enormous latitude to determine which services, programs, and employees can be sidelined, decisions that could go far beyond what has occurred during past shutdowns."
Beyond the Antideficiency Act, which says the government cannot spend money or incur debts without Congress' authority, the shutdown process has historically been guided by traditions, not laws.
In recent past shutdowns, hundreds of thousands of employees were furloughed, but the shutdowns did not result in mass permanent layoffs or significant reorganizations. Under federal law, federal workers also receive back pay for their time on furlough.
Trump and his congressional allies would be in charge of the government amid a shutdown. What can Trump do on his own?
OMB told agencies to 'consider' layoff notices
The Trump administration has already reduced the workforce by about 200,000, a number that could grow to 300,000 by the end of the year, Stier wrote. The administration gutted some agencies and programs including the Consumer Financial Protection Bureau and Voice of America.
OMB provided an email, first published by Politico, that it sent to agency heads that said agencies should consider sending "reduction in force" notices to employees whose programs are "not consistent with the President's priorities" or lack mandatory funding or another source of funding, such as the tax and spending legislation H.R. 1, which became law in July.
Rachel Greszler, a workforce expert at the conservative Heritage Foundation, said the administration hasn't mandated layoffs, but directed agencies to "consider" issuing such notices "as a way to let federal employees know which of their jobs could be on the line if Congress reduces their agency's funding."
WATCH: White House threatens mass federal firings if Congress fails to avoid a shutdown
This signals to Democrats that health care funding demands could backfire, she said, potentially causing further reductions in the size of the federal government.
Several questions remain, including how many employees could face layoffs and when. The memo says once fiscal year 2026 appropriations are enacted, agencies should revise their plans to reduce staff.
"I believe this memo indicates OMB will pursue a dual path of shutdown-related furloughs and a separate process of mass layoffs," Sewell said. Whether the layoffs happen before or after funding is restored "is an open question," Sewell said. "This certainly indicates the administration wants to cut these agencies and programs at any opportunity either now or in the future."
Experts offered mixed opinions about whether layoffs would hold up in court. Any such process must follow the rules, such as a 60-day written notice.
"A shutdown provides no new legal authority to engage in widespread firings," said Sam Berger, who works for the liberal Center on Budget and Policy Priorities and who worked at OMB during the Biden and Obama administrations.
Sen. Chuck Schumer, the Democratic Senate minority leader from New York, said the memo is an "attempt at intimidation" and predicted such firings would be reversed.
Social Security checks and other mandatory spending will continue
Mandatory spending — ongoing spending that does not require periodic extensions from Congress — generally continues during a shutdown. This means Americans would still receive Social Security checks and be able to use Medicare and Medicaid.
In previous shutdowns, border protection, medical care in hospitals, air traffic control, law enforcement and power grid maintenance were deemed essential and remained active during the shutdown.
Even continued services can be disrupted. During the 2018-19 shutdown, holiday travelers faced delays as many unpaid TSA staff and air traffic controllers didn't come to work.
Administrations have a lot of leeway to define "essential" workers. During the 2013 shutdown, the Obama administration closed national parks. In 2018, the Trump administration kept many national parks open with limited services using previously paid park entrance fees to cover personnel costs; the Government Accountability Office concluded that this violated federal law.
The second-term Trump administration is expected to continue priorities such as immigration enforcement and might try to focus cuts on areas that have already been slashed. Trump campaigned on a promise to abolish the Education Department, and his administration has shrunk the Environmental Protection Agency.
There have been four shutdowns in recent decades that lasted more than one business day, according to the Committee for a Responsible Federal Budget.