When will Biden ask the Supreme Court to uphold Obamacare?

For four years the law remained a consistent target at the center of former President's Donald Trump's political dart board.

His ire culminated a little more than three months ago, when acting Solicitor General Jeffrey B. Wall told the justices that they should invalidate the entire 900-page law.

The challenge for Biden's Justice Department is not only telling the justices it manifestly opposes the position taken by the Trump administration in the case, but how to pull off the task. Changing its position on the Affordable Care Act wouldn't end the lawsuit, which was brought by Texas and other Republican-led states, but could inform how the justices look at the case.

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Biden's new acting solicitor general is Elizabeth Prelogar, who is likely recused from the issue because as a private lawyer she filed a brief on behalf of 47 senators in support of the law. That means if the solicitor general's office files a supplemental brief, or a missive to the court, it will likely be handled by a career employee.

Already, Prelogar has asked the Supreme Court to remove two cases from the court's February calendar because they concern Trump policies on the issue of funding for the border wall as well as immigration that Biden has vowed to change.

When to change positions

Recently, three powerful former members of the Office of Solicitor General, a small cadre of top-notch appellate lawyers who argue the government's position before the Supreme Court, have made clear that there are times when the head or acting head of the Office should not shy away from a change of position.

To be sure, the solicitor general's office, comprised of political and career lawyers, prides itself in representing long-term institutional interests of the United States, not the political whim of a particular president. As such, its interest in the stability of the law and its own credibility before the justices is paramount and a change of position based on a new administration has been institutionally considered a rare move. But Trump may have pushed that norm.

The heart of the Affordable Care Act dispute dates back to 2012 when Chief Justice John Roberts stunned conservatives by upholding the law under Congress' taxing power, even though that justification for the law had hardly came up during oral arguments. At the time, Paul Clement, who had served as solicitor general for former President George W. Bush, was in private practice representing 26 states opposed to the law. Clement's side lost.

Asked later at a 2013 speech before Marquette University Law School if he would have done anything differently Clement joked: "Sure, I'd start with the taxing power."

Flash forward to 2017 when Congress brought the tax penalty down to zero. Critics of the Affordable Care Act raced to court and argued that Congress had gotten rid of the legal underpinning of the individual mandate, so the rest of the law should fall with it.

A district court judge invalidated the mandate, and said it was inseverable from the rest of the law. His decision was put on hold, but it emboldened the Trump administration to dig in and escalate its case against the law. Instead of continuing to argue that the mandate and other closely related provisions should fall, the Trump administration endorsed most of the position taken by Texas and other states that the whole fall should fall.

"The individual mandate cannot be severed from the remainder of the Affordable Care Act," Trump's DOJ said in court briefs.

The case, argued on November 10, is now pending before the justices.

In a talk hosted by Georgetown Law last week, Clement -- the man who argued against the law for a very different challenge in 2012-- expressed concern about the position taken by Trump's DOJ when it comes to the legal doctrine of "severability," a key component of the challenge at hand.

"It has been the long-term position of the Justice Department to defend the constitutionality of statutes whenever reasonable arguments can be made," Clement said. He was quick to add that it has also been understood that "even if you think that part of the statute is unconstitutional, it would be in the long-term tradition of the office to have as little of the statute as possible fall."

"The Justice Department in my view tends to get itself in trouble when it deviates from that tradition," Clement said in comments that amounted to repudiation of the Trump administration's legal position in the case.

Neal Katyal, a former acting solicitor general during the Obama administration agreed with Clement's take on severability during the same talk .

Changing position is not something "you do lightly," he said, "but this case, you and I are agreeing on this, I mean I think it fits it to a T."

Instead of just focusing on the individual mandate, Katyal noted, the Trump administration argued "the entire kit and caboodle" should be struck.

He added: "I can't think of any solicitor general living or dead who would take that position, and yet they did."

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Michael R. Dreeben, who served in the Office of the Solicitor General for more than 30 years, including 24 years as the as the deputy solicitor general in charge of the government's criminal docket in the Supreme Court had a slightly less conservative take than Clement and Katyal when it comes to switching positions. Dreeben's tenure spanned 14 solicitors general and acting solicitors general. In a recent piece for the Yale Law Journal, he spoke up about the practice of changing positions, but never mentioned the Affordable Care Act directly.

He suggested that reversals could not be done "lightly or frequently" but he noted that Trump's Solicitor General had taken dramatic shifts in position and often prevailed before the justices.

Dreeben noted that in its first full term at the Supreme Court during the Trump administration the office of Solicitor General made four major shifts in high profile cases. "These reversals were abrupt and appeared strikingly at odds with institutional norms," he wrote. But the Trump administration prevailed in all of the cases including one concerning public sector unions that overturned some 40-year old precedent.

"Consistency is a virtue -- up to a point," Dreeben said.