Justice Antonin Scalia voiced this skepticism early, pointing out that in order for the Anti-Injunction Act to be triggered, the statute would need to clearly identify the penalty as a tax, which it does not. "Unless it's clear, courts are not deprived of jurisdiction, and I find it hard to think that this is clear," Scalia said.
The Affordable Care Act describes the fine not as a revenue-raising mechanism but as a backstop penalty.
"Congress has nowhere used the word tax. What it says is penalty," said Justice Stephen Breyer. "It's collected in the same manner as a tax. But that doesn't automatically make it a tax." The law, he added, "doesn't use the word tax once, except as a collection device."
Obama-appointed Justices Sonia Sotomayor and Elena Kagan questioned the limits and exceptions under the Anti-Injunction Act. They pressed the counsel tasked with defending the AIA argument, Robert Long, to cite where the Affordable Care Act statute suggests that Congress intended for the mandate to be a tax.
Justice Ruth Bader Ginsburg seemed clearer in her view. "This is not a revenue-raising measure," she said, "because if it is successful, nobody will pay the penalty, and there will be no revenue to raise."
The justices called on the lawyers for the White House and the Republicans to make the case that the Supreme Court has the requisite jurisdiction. Chief Justice John Roberts and Justices Samuel Alito and Anthony Kennedy were less vocal than the liberal-leaning justices. Justice Clarence Thomas, as expected, did not speak.
Notably, Roberts -- who some court watchers believe may want to punt the ruling beyond an election year, to shield the Supreme Court from political attacks -- only asked a handful of questions and did not seem to indicate that he believes the mandate is a tax.
"It's a command," Roberts said at one point. "A mandate is a command."