White House press secretary Jen Psaki ended Tuesday’s press briefing with a quick exchange: “Thank you, Jen,” said Josh Boak, a White House reporter for the Associated Press. “Great,” replied Psaki. Then she put on her mask and headed out.

Those four words signaled the resurrection of an old White House briefing room tradition — observed under both Democratic and Republican administrations — in which the press secretary awaits the nod of the attending AP reporter before closing the book. (The privilege was initially assigned to the senior wire correspondent, but it eventually turned into an exclusively AP role.) Whereas her predecessor, Kayleigh McEnany, often ended briefings with scripted attacks on the media, Psaki has embraced a custom that accords the media a voice in the management of the briefing room.

George Condon, a National Journal White House reporter on the beat since 1982, described the traffic-cop role of longtime United Press International reporter Helen Thomas: “Before she would say, ‘Thank you,’ she was in the first row and she would glance around to see if there were hands still up because she didn’t want to cut it off before people had a chance to ask questions,” Condon said. Terence Hunt, a former AP White House reporter, tells us that the practice goes back at least 75 years, citing a 1946 book by longtime UPI reporter Merriman Smith, titled “Thank You, Mr. President” in reference to Smith’s role in closing out presidential news conferences.

The procedure vests a fair bit of power in a single correspondent, who risks permitting the press secretary’s exit before everyone has had a chance to ask a question. Hunt usually waited 45 minutes or an hour before giving the nod. It is possible to wait too long: One White House correspondent recalled pinging the AP correspondent during an Obama-era briefing to shut it down.

Not that the length was an issue for the press secretary at the time, Josh Earnest. “I was conscious of making clear that I wasn’t afraid to answer all those questions, even the tough ones,” says Earnest, who averaged 76 minutes per press briefing. “I thought that projecting that kind of confident body language was an important part of the job, and even after the AP says, ‘Thank you,’ taking more questions after that.” Earnest recalls that journalists told him that he had a knack for going over time. “I would just assure them all that it was okay with me that if they had an urgent reason to go, stand up and leave.”

The Trump-era press secretaries replaced courtesy with hostility. The problem wasn’t just that McEnany and her predecessors advanced the president’s lies, sneered at the assembled correspondents, endorsed their boss’s enmity toward the First Amendment and failed to reliably represent the president. It was also that they didn’t stand at the lectern long enough to exhaust the questions of the press corps.

So the tradition died — until the Biden administration. On Tuesday, Psaki started the session by calling on Boak. After more than 45 minutes, Psaki answered a question about the Biden administration’s policy on tariffs. She finished her response and got the signal from Boak.

Asked about these moves, Psaki replied in an email, “We have every intention of continuing to look for ways to modernize and be far less traditional, but this tradition sets the right tone of a wire service that is carried in media outlets across the country kicking off the briefing and also signaling when it is time to end.”

More than 15,000 news outlets worldwide, indeed, use AP content. According to Condon, the tradition of calling on a wire service in the briefing room predated the arrival of TV news. “When it started, the wires had by far the biggest audience, biggest readership,” notes Condon. “They also had a tradition of fairness and evenhandedness. No other reporter could complain about them being first. Almost all newspapers were either members or subscribers.”

In the age of texting, the AP reporter at White House briefings has to juggle two tasks: putting good questions before the press secretary and sifting through the messages about when to say, “Thank you.” AP Washington Bureau Chief Julie Pace, who covered the White House for nine years, says that she’d get nudges from both reporters and White House press aides on when to wrap a session. “So you were just always watching the clock, trying to make sure that you got everybody in.”

The courtesy is about more than just manners, argues Pace. “It puts power back in the hands of the press, which is where you want it to be,” she says. “This is our press room. The press secretary is stepping out into our press room. We should control the rhythm of that room.”

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