Royal etiquette for the Trumps' visit: Don't kiss the queen

President Donald Trump is coming to Britain fresh from a confrontational NATO summit that featured stinging criticism of America's closest allies, but he's likely to tone down that stance when he takes tea Friday with Britain's Queen Elizabeth II.

FILE - In this July 3, 2018 file photo, President Donald Trump arrives to speak to a "Salute to Service" dinner in White Sulphur Springs, W.Va. Trump enjoys flouting diplomatic rules and expressing himself in bold and sometimes mocking tweets and comments, but that side of his personality is unlikely to surface when he takes tea Friday, July 13, 2018 with Queen Elizabeth II. The president and his wife Melania are not expected to make waves during the visit with the 92-year-old monarch, who has met every U.S. president since Dwight Eisenhower with the exception of Lyndon Johnson, who never visited Britain while in office. (AP Photo/Evan Vucci, File)

The president and his wife, Melania, are not expected to make waves during the visit with the 92-year-old monarch. Elizabeth has met every U.S. president since Dwight Eisenhower with the exception of Lyndon Johnson, who never visited Britain while in office.

The imposing setting at Windsor Castle and the fact that his hostess is one of the most admired women in the world are expected to temper Trump's iconoclastic ways. There are also rules of etiquette for encounters with the queen, although they are less rigid than many believe.

FILE - In this Wednesday, May 25, 2011 file photo, US President Barack Obama and first lady Michelle Obama welcome Britain's Queen Elizabeth II for a reciprocal dinner at Winfield House in London. US President Trump enjoys flouting diplomatic rules and expressing himself in bold and sometimes mocking tweets and comments, but that side of his personality is unlikely to surface when he takes tea Friday, July 13, 2018 with Queen Elizabeth II. The president and his wife Melania are not expected to make waves during the visit with the 92-year-old monarch, who has met every U.S. president since Dwight Eisenhower with the exception of Lyndon Johnson, who never visited Britain while in office. (AP Photo/Charles Dharapak, File)

Chief among them: Don't get too affectionate with the queen, who does not expect to be hugged or kissed by guests.

In a meeting like this, etiquette requires Trump to wait until the queen offers her hand, then to shake it politely and move on. The same applies to Mrs. Trump.

Neither the president nor the first lady would be likely to bow or to curtsy when they meet the queen, said Hugo Vickers, an author who has long chronicled the British royals.

FILE - In this Wednesday, 15, 1991 file photo, US President George H.W. Bush escorts Queen Elizabeth II from the White House to a helicopter enroute to Baltimore to watch her first major league baseball game, in Washington. US President Trump enjoys flouting diplomatic rules and expressing himself in bold and sometimes mocking tweets and comments, but that side of his personality is unlikely to surface when he takes tea Friday, July 13, 2018 with Queen Elizabeth II. The president and his wife Melania are not expected to make waves during the visit with the 92-year-old monarch, who has met every U.S. president since Dwight Eisenhower with the exception of Lyndon Johnson, who never visited Britain while in office. (AP Photo/Doug Mills, File)

"That wouldn't be required from a head of state or the wife of a head of state," he said. "He would be wise not to attempt to kiss her, and I don't expect for a moment that he will."

Trump said in a newspaper interview that he's not nervous about meeting the queen, who he called "a tremendous woman."

"I really look forward to meeting her. I think she represents her country so well," he told The Sun.

FILE - In this file photo dated May 1977, U.S. President Jimmy Carter, right, and Britain's Queen Elizabeth II with French President Valery Giscard d'Estaing, at Buckingham Palace in London. US President Trump enjoys flouting diplomatic rules and expressing himself in bold and sometimes mocking tweets and comments, but that side of his personality is unlikely to surface when he takes tea Friday, July 13, 2018 with Queen Elizabeth II. The president and his wife Melania are not expected to make waves during the visit with the 92-year-old monarch, who has met every U.S. president since Dwight Eisenhower with the exception of Lyndon Johnson, who never visited Britain while in office. (AP Photo, File)

Vickers expects the royal visit to go smoothly despite the many controversies swirling around Trump's visit to the U.K. He says the queen will form an impression of the American president but will not share it, given her penchant for keeping her thoughts to herself and her very closest family.

"Whatever we think of President Trump, he is the elected president of the United States of America and he has been invited to this country and he must be treated with great civility," Vickers said. "The queen will obviously be very courteous to him."

There are conventions for how to address the queen. The Trumps will be expected to call her "Your Majesty" upon meeting her and afterward call her "Ma'am."

FILE - In this Saturday, June 4, 1994 file photo, Britain's Queen Elizabeth smiles, as she sits alongside President Bill Clinton at a dinner in the Guildhall in Portsmouth, England, commemorating the 50th anniversary of D-Day. US President Trump enjoys flouting diplomatic rules and expressing himself in bold and sometimes mocking tweets and comments, but that side of his personality is unlikely to surface when he takes tea Friday, July 13, 2018 with Queen Elizabeth II. The president and his wife Melania are not expected to make waves during the visit with the 92-year-old monarch, who has met every U.S. president since Dwight Eisenhower with the exception of Lyndon Johnson, who never visited Britain while in office. (AP Photo/Doug Mills, File)

But the queen certainly was not upset when South African President Nelson Mandela called her Elizabeth. Nor was she miffed when Michelle Obama put her arm around the queen briefly.

Elizabeth, the longest reigning monarch in British history, has shown herself to be unflappable when the unexpected occurs. She is not known to show anger in public, and the only times most people have seen her show unbridled glee is when one of her racehorses performs extremely well in a competition.

FILE - In this Wednesday, April 1, 2009 file photo, Michelle Obama, wife of U.S. President Barack Obama, left, walks with Britain's Queen Elizabeth II at the reception at Buckingham Palace in London. US President Trump enjoys flouting diplomatic rules and expressing himself in bold and sometimes mocking tweets and comments, but that side of his personality is unlikely to surface when he takes tea Friday, July 13, 2018 with Queen Elizabeth II. The president and his wife Melania are not expected to make waves during the visit with the 92-year-old monarch, who has met every U.S. president since Dwight Eisenhower with the exception of Lyndon Johnson, who never visited Britain while in office. (Daniel Hambury, Pool Photo via AP, File)

The public usually sees her in maximum composure mode.

She didn't complain, for example, in 1991 when poor White House planning meant that only her hat was visible when she addressed a crowd in Washington along with President George H.W. Bush — the podium height had been set for the tall president, not the diminutive monarch.

The queen is known to dislike revealing clothing, so it is expected that Mrs. Trump will wear a fashionable but conservative outfit. The president is likely to wear his traditional blue suit and a tie.

FILE - In this file photo dated Oct. 17, 1957, President Dwight Eisenhower, second left and first lady Mamie, second right are flanked by their royal guests, Britain's Queen Elizabeth II and her husband, Prince Philip, at the White House, in Washington. US President Trump enjoys flouting diplomatic rules and expressing himself in bold and sometimes mocking tweets and comments, but that side of his personality is unlikely to surface when he takes tea Friday, July 13, 2018 with Queen Elizabeth II. The president and his wife Melania are not expected to make waves during the visit with the 92-year-old monarch, who has met every U.S. president since Dwight Eisenhower with the exception of Lyndon Johnson, who never visited Britain while in office. (AP Photo, File)

Some standard rules apply — it's considered poor form to turn your back on the queen or to photograph her. Still, the days when there was a "proper" or "improper" way to hold a tea cup disappeared at about the time of the Beatles.

"Those days are long gone," said Joe Little, managing editor of Majesty magazine. "As long as he doesn't drink it out of the saucer. That's sort of a British, a London tradition, but it's frowned upon."

He said the entire event will be much more relaxed than a formal banquet or lunch.

FILE - In this file photo dated July 7, 1976, U.S. President Gerald Ford dances with Britain's Queen Elizabeth II in the State Dining Room at the White House, following a State Dinner in the queen's honor. US President DonaldTrump enjoys flouting diplomatic rules and expressing himself in bold and sometimes mocking tweets and comments, but that side of his personality is unlikely to surface when he takes tea Friday, July 13, 2018 with Queen Elizabeth II. The president and his wife Melania are not expected to make waves during the visit with the 92-year-old monarch, who has met every U.S. president since Dwight Eisenhower with the exception of Lyndon Johnson, who never visited Britain while in office. (AP Photo/John Duricka, File)

It will not be a prolonged visit, like the one in 1982 that was long enough to allow Ronald Reagan to go horseback riding with the queen.

There is one thing the Trumps should keep in mind, however: If you don't like dogs, pretend that you do, even if it's only for an hour.

FILE - In this 1970 file photo, Britain's Queen Elizabeth II, left, reacts with U.S. President Richard Nixon, at Chequers, in Buckinghamshire, England. US President Donald Trump enjoys flouting diplomatic rules and expressing himself in bold and sometimes mocking tweets and comments, but that side of his personality is unlikely to surface when he takes tea Friday, July 13, 2018 with Queen Elizabeth II. The president and his wife Melania are not expected to make waves during the visit with the 92-year-old monarch, who has met every U.S. president since Dwight Eisenhower with the exception of Lyndon Johnson, who never visited Britain while in office. (AP Photo, File)

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:

The court marshal will bang the gavel at 10 a.m. EDT and Chief Justice John Roberts will announce soon after 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.

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.

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.

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.”

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.

Associated Press writer Mark Sherman contributed to this report.

FILE - Members of the Supreme Court sit for a new group portrait following the addition of Associate Justice Ketanji Brown Jackson, at the Supreme Court building in Washington, on Oct. 7, 2022. Bottom row, from left, Associate Justice Sonia Sotomayor, Associate Justice Clarence Thomas, Chief Justice of the United States John Roberts, Associate Justice Samuel Alito, and Associate Justice Elena Kagan. Top row, from left, Associate Justice Amy Coney Barrett, Associate Justice Neil Gorsuch, Associate Justice Brett Kavanaugh, and Associate Justice Ketanji Brown Jackson. The core issue being debated before the Supreme Court on April 25, 2024, boils down to this: Whether a former president is immune from prosecution for actions taken while in office — and, if so, what is the extent of the immunity? (AP Photo/J. Scott Applewhite)

FILE - The Supreme Court of the United States is seen in Washington, March 26, 2024. The Supreme Court is hearing arguments this week with profound legal and political consequences: whether former President Donald Trump is immune from prosecution in a federal case charging him with plotting to overturn the results of the 2020 election. (AP Photo/Amanda Andrade-Rhoades, File)

FILE - President Donald Trump arrives to speak at a rally in Washington, on Jan. 6, 2021. The Supreme Court will hear arguments over whether Trump is immune from prosecution in a case charging him with plotting to overturn the results of the 2020 presidential election. (AP Photo/Jacquelyn Martin, File)