The U.S. Supreme Court on Thursday took up Donald Trump’s bid to avoid prosecution over his efforts to overturn his 2020 election loss to Democrat Joe Biden.

Trump’s lawyers argue that former presidents are entitled to absolute immunity for their official acts. Otherwise, they say, politically motivated prosecutions of former occupants of the Oval Office would become routine and presidents couldn’t function as the commander in chief if they had to worry about criminal charges.

Lower courts have rejected those arguments, including a unanimous three-judge panel on an appeals court in Washington. And even if the high court resoundingly follows suit, the timing of its decision may be as important as the outcome.

Some Supreme Court justices posed scenarios or expressed skepticism Thursday as arguments started in Donald Trump’s bid to avoid prosecution over his efforts to overturn his 2020 election loss to Democrat Joe Biden.

Conservative Justice Samuel Alito said he considered it “implausible” that a president could legally order Navy SEALs to order the assassination of a political rival. That skepticism matters because the hypothetical is something the Trump team, which includes attorney D. John Sauer, has suggested could theoretically be protected from prosecution.

Conservative Justice Amy Coney Barrett asked Sauer a question that cut to the heart of the case, reading aloud allegations from the indictment and asking him to respond whether Trump’s actions in each instance were private or official.

Trump’s attorneys concede that immunity does not extend to personal actions but instead protects official acts. Sauer said he believed most of the acts are unquestionably official.

Chief Justice John Roberts, who could be a key swing vote, struck a skeptical note about the idea of expunging from the indictment acts that are official rather than personal, saying such a move would render the case a “one-legged stool.”

Liberal Justice Ketanji Brown Jackson said Sauer was asking for a change in the immunity law. She raised Richard Nixon’s pardon, asking, “I think that if everybody thought that presidents couldn’t be prosecuted, then what was that about?”

Liberal Justice Elena Kagan noted the Founding Fathers did not insert an immunity clause for presidents into the Constitution — but, she said, “they knew how to.”

Supreme Court Justice Clarence Thomas pressed Donald Trump’s lawyer D. John Sauer at the outset of arguments Thursday, asking where the principle of absolute immunity comes from.

The question was the first during arguments at the Supreme Court in Trump’s bid to avoid prosecution over his efforts to overturn his 2020 election loss to Democrat Joe Biden.

A skeptical Justice Sonia Sotomayor pointedly noted to Sauer that the indictment alleges that Trump acted for personal gain.

She said the Founding Fathers had contemplated the idea of immunity for presidents but had explicitly decided against it.

She made clear her opposition to the Trump legal team’s position, saying she was having a hard time envisioning immunity for a president who creates and submits false documents, orders the assassination of a political rival, and any number of other criminal acts.

“If the president decides that his rival is a corrupt person and he orders the military, or he orders someone, to assassinate him, is that within his official acts for which he can get immunity?” Sotomayor asked.

“It would depend on the hypothetical, but we could see that could well be an official act,” Sauer replied.

AL.com contributed to this report.