Sauer argued it could.

“It would depend on the hypothetical. We can see that could well be an official act,” Saur replied.

Sotomayor interjected, “It could, and why? Because he’s doing it for personal reasons.”

“And isn’t that the nature of the allegations here, that he’s not doing these acts in furtherance of an official responsibility, he’s doing it for personal gain?” Sotomayer asked.

Sauer followed up, “I agree with that characterization of the indictment and that confirms immunity.”

Sauer and the justices spent some time Thursday morning debating whether certain hypothetical situations would be considered “private acts” or “official acts” under Sauer’s argument.

Justice Elena Kagan asked Saur: “If a president sells nuclear secrets to a foreign adversary, is that immune?”

Saur argued that if it were “structured as an official, he would have to be impeached and convicted first.”

At the outset, Saur argued before the nine justices of the Supreme Court, “Without presidential immunity from criminal prosecution, there can be no presidency as we know it.”

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“If a president can be charged, put on trial, and imprisoned for his most controversial decisions as soon as he leaves office, that looming threat will distort the president’s decision-making precisely when bold and fearless action is most needed,” Saur said.

Saur continued, “Could President George W. Bush have been sent to prison for obstructing an official proceeding or allegedly lying to Congress to induce war in Iraq? Could President Obama be charged with murder for killing US citizens abroad by drone strike? Could President Biden someday be charged with unlawfully inducing immigrants to enter the country illegally for his border policies?”

“The answer to all these questions is no,” he said.

Meanwhile, Justice Department lawyer Michael Dreeben told the justices that the high court has never recognized absolute criminal immunity for any public official.

“Petitioner, however, claims that a former president has permanent criminal immunity for his official acts, unless he was first impeached and convicted,” Dreeben said of Trump’s arguments. “His novel theory would immunize former presidents for criminal liability for bribery, treason, sedition, murder, and, here, conspiring to use fraud to overturn the results of an election and perpetuate himself in power.”

“Such presidential immunity has no foundation in the Constitution,” Dreeben told the court. “The framers knew too well the dangers of a king who could do no wrong. They, therefore, devised a system to check abuses of power, especially the use of official power for private gain.”

Justice Clarence Thomas asked the first question to Dreeben, saying, “Are you saying there is no presidential immunity even for official acts?”

Dreeben responded, “yes,” but noted that a president can assert “Article II objections to criminal laws that interfere with an exclusive power possessed by the president or that prevent the president from accomplishing his constitutionally assigned functions.”

The nation’s highest court will weigh whether to fully or even partially support Trump’s unprecedented claim of presidential immunity, which protects former presidents from facing criminal charges if their actions were related to the job.

It’s unclear when the Supreme Court will release its decision on Trump’s claims. If the justices adhere to their normal schedule, a ruling would be released at the end of June. Special counsel Jack Smith has urged justices to deal with the former president’s case quickly so the trial over Trump’s underlying charges related to trying to overturn the 2020 presidential election can proceed.

Trump’s trial was supposed to have begun last month, but depending on how the Supreme Court rules in this case, it could be delayed past the election. Legal observers have repeatedly pointed out that the former president could count it as a victory even if justices reject his sweeping immunity claims if their decision takes up more time. If Trump were to win the election in November, he could even find ways to scuttle Smith’s prosecution entirely.

As of now, Trump’s Manhattan hush-money trial is his only criminal trial to have started. Trump could not attend oral arguments at the Supreme Court due to the New York trial, in which he stands charged with 34 counts of business fraud related to hush-money payments made to porn star Stormy Daniels.

His other cases, including another Smith-led case focused on Trump’s hoarding of classified documents, don’t yet have trial dates and are unlikely to be tried before the election.

The justices could also fundamentally change the presidency itself. Never before has a former president faced criminal prosecution. Their ruling could have sweeping effects on the future of the presidency, particularly if they accept some of Trump’s argument that a Nixon-era Supreme Court decision on civil immunity applies to criminal charges as well. Smith and many legal scholars have argued that such immunity could empower the presidency to the point where the nation’s highest office in the land would be above the law the executive branch is required to enforce.

Trump and his allies have repeatedly hinted that if immunity is not granted, they may try to prosecute President Joe Biden as a form of retribution.

The former president has never been shy about suggesting his political rivals should be sent to prison.