CNN  — 

The Trump administration offered its first full argument Wednesday for its reversal on the Affordable Care Act, arguing in new court filings that the entire law “should not be allowed to remain in effect.”

The government argues in the filings that the so-called “individual mandate” requiring Americans to have coverage is unconstitutional and that the rest of the law should therefore also be struck down, even if the government “might support some individual provisions as a policy matter.”

The landmark legislation provides health care coverage to millions of Americans.

In the filing, Assistant Attorney General Joseph Hunt acknowledged that the administration had previously argued that parts of the law could remain in effect even if the individual mandate were struck down, but he said, the administration had come to believe it could no longer defend that position. He suggested that rewriting the statute by “picking and choosing which provisions to invalidate” would interfere with the role of Congress and the “proper course” for the courts would be to strike down the law in its entirety.

The brief was filed with the conservative-leaning 5th US Circuit Court of Appeals, which will hear arguments in July and possibly tee up a Supreme Court case next term that could finally decide the fate of the law and render a decision during the heart of the presidential election.

If the law is struck down, it would be a major victory for President Donald Trump, who has worked his entire presidency to wipe away a signature legislative achievement of the Obama administration.

Last month, the President tweeted that Republicans were developing a “really great” health care plan with “far lower premiums” than Obamacare and that a vote will be taken “right after” the election.

The administration’s reversal came after District Judge Reed O’Connor ruled in favor of several Republican state attorneys general and governors in December and held that the entire law must fall. O’Connor, who sits on the US District Court for the Northern District of Texas, put his ruling on hold pending appeal.

The new position has drawn criticism from supporters of the law as well as some opponents.

“The Department of Justice disregarded its own long-standing norms and practices in refusing to defend a readily defensible federal law and failing to urge the court to dismiss this case in the first place,” said Jonathan H. Adler, a professor of law at Case Western Reserve University School of Law who is no fan of the health care law but has questioned the current legal challenge, on Wednesday.

Wednesday’s 50-page filing expands on the government’s new legal position.

“Allowing some of the reforms to go into effect without others with which they are inextricably linked would not be giving effect to the statute but rewriting it, which is the prerogative of Congress rather than the courts,” Hunt wrote.

If the appeals court agrees, it would wipe away the “guaranteed issue” and “community rating” provisions, which pertain to preexisting conditions, but it would also invalidate other parts of the law – such as Medicaid expansion – that have nothing to do with the individual mandate.

Senate Minority Leader Chuck Schumer, a New York Democrat, called the administration’s brief “heartless and wrong” on Wednesday.

“This action only proves President Trump and his Department of Justice would rather make political points than defend our health care law that protects the 133 million Americans with pre-existing conditions, has provided tens of millions more Americans with health insurance coverage, and has lowered prescription drug costs for millions of seniors,” Schumer said in a statement. “President Trump wants to take all of that away from the American people, jacking up health care costs and leaving millions without coverage.”

House Speaker Nancy Pelosi, a California Democrat, also responded.

“There is no viable legal argument and no moral defense for the devastation the Trump Administration is asking the court to inflict on Americans’ health care,” her statement says. “The Trump Administration owes the American people answers for why it is seeking to rip away protections for pre-existing conditions and cause such vast suffering for families across America.”

The case challenging the law is brought by 18 Republican state attorneys general and governors, as well as two individuals. They argued that Congress effectively eliminated the individual mandate penalty by reducing it to $0 as part of the 2017 tax cut bill. The mandate requires nearly all Americans to get health insurance or pay a penalty.

Texas Attorney General Ken Paxton – a leader of the coalition of challengers – argued that Congress’ action undercut the legal justification for the individual mandate, which had been upheld by the Supreme Court under the taxing power, and as a result rendered the central provision unconstitutional.

“The case is not about whether the ACA is good or bad policy,” Paxton argued in briefs also filed Wednesday, “it is about the constitutional limits on our federal government and the proper text-based interpretation statutes.”

California Attorney General Xavier Becerra, leading a coalition of 20 Democratic states, stepped in to defend the law when the administration declined to do so, arguing not only that the individual mandate remains constitutional but that even if it were struck down the rest of the law could stand. Becerra called the district court opinion an “assault on 133 million Americans with preexisting conditions.”

The Democratic-led House of Representative now also is defending the law.

During congressional testimony in April, Attorney General William Barr defended the administration’s new legal position even though it reportedly had triggered disagreement within the administration.

Barr was grilled about using the Justice Department’s resources to take a stance that, if successful, would leave uninsured tens of millions of Americans who depend on the Obamacare exchanges and Medicaid expansion for their coverage.

“If you think it’s such an outrageous position, you have nothing to worry about. Let the courts do their job,” Barr told Rep. Matt Cartwright, a Pennsylvania Democrat, at a House Appropriations Committee hearing about the department’s budget.

This story has been updated.