WASHINGTON (AP) — The Supreme Court hears arguments Thursday over whether Donald Trump is immune from prosecution in a case charging him with plotting to overturn the results of the 2020 presidential election.

It's a historic day for the court, with the justices having an opportunity to decide once and for all whether former presidents can be prosecuted for official acts they take while in the White House.

But between a decades-old court case about Richard Nixon, and an obscure constitutional provision about presidential impeachments, there are likely to be some unfamiliar concepts and terms thrown about.

Here are some tips to help follow everything:

WHEN DOES THE SESSION START?

The court marshal will bang the gavel at 10 a.m. EDT and Chief Justice John Roberts will announce the start of arguments in Donald J. Trump vs. United States of America, as the case is called.

The session easily could last two hours or more.

WHERE DO I FIND THE LIVESTREAM?

There are no cameras in the courtroom, but since the pandemic the court has livestreamed its argument sessions. Listen live on apnews.com/live/trump-supreme-court-arguments-updates or the court's website at www.supremecourt.gov. C-SPAN also will carry the arguments at www.c-span.org.

IMPEACHMENT CLAUSE

Expect to hear talk about the impeachment process and the relationship, if any, to criminal prosecution.

Central to Trump's immunity argument is the claim that only a former president who was impeached and convicted by the Senate can be criminally prosecuted. Trump was impeached over his efforts to undo the election in the run-up to the violent riot at the U.S. Capitol on Jan. 6, 2021. But he was acquitted, not convicted, by the Senate in 2021.

Trump's lawyers cite as backup for their argument a provision of the Constitution known as the Impeachment Judgment Clause that says an officeholder convicted by the Senate shall nevertheless be "liable and subject to indictment, trial, judgment and punishment" in court.

Prosecutors say the Trump team is misreading the clause and that conviction in the Senate is not a prerequisite for a courtroom prosecution.

WAIT, WHAT'S THIS ABOUT RICHARD NIXON?

There's going to be plentiful discussion about Nixon but not necessarily for the reasons one might think.

Trump's team has repeatedly drawn attention to a 1982 case, Nixon v. Fitzgerald, in which the Supreme Court held that a former president cannot be sued in civil cases for their actions while in office. The case concerned the firing of an Air Force analyst, A. Ernest Fitzgerald, who testified before Congress about cost overruns in the production of a transport plane.

Fitzgerald's lawsuit against Nixon, president at the time of the 1970 termination, was unsuccessful, with Justice Lewis Powell writing for the court that presidents are entitled to absolute immunity from civil lawsuits for acts that fall within the "outer perimeter" of their official duties.

Importantly, that decision did not shield presidents from criminal liability, though Trump's team says the same analysis should apply.

Special counsel Jack Smith's team is also likely to bring up a separate Supreme Court decision involving Nixon that they say bolsters their case — a 1974 opinion that forced the president to turn over incriminating White House tapes for use in the prosecutions of his top aides.

Prosecutors have also noted that Nixon accepted rather than declined a subsequent pardon from President Gerald Ford — a recognition by the men, they say, "that a former President was subject to prosecution."

DRONE STRIKES AND SEAL TEAM SIX

The justices are known to love presenting hypothetical scenarios to lawyers as a way of testing the outer limits of their arguments. Expect that practice to be on full display Thursday as the court assesses whether former presidents are entitled to absolute immunity.

Already, Trump's lawyers have warned that if the prosecution is permitted to go forward, it would open the floodgates to criminal charges against other presidents, such as for authorizing a drone strike that kills a U.S. citizen or for giving false information to Congress that leads the country into war.

In a memorable moment during arguments in January before a federal appeals court, a judge asked a Trump lawyer whether a president who ordered a Navy SEAL to assassinate a political rival could be prosecuted.

Look for Smith's team to try to draw a sharp distinction between acts that it says are quintessential exercises of presidential power — such as ordering a drone strike during war — to the acts that Trump is accused of in this case, such as participating in a scheme to organize fake electors in battleground states. Those acts, prosecutors say, are personal acts and not presidential ones.

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Associated Press writer Mark Sherman contributed to this report.