Body language can say a lot. Here's what one expert told us after studying Kamala Harris's and Pete Buttigieg's interactions on their joint trip to Charlotte.

• Vice President Kamala Harris and Transporation Secretary Pete Buttigieg's relationship is under the microscope.

• A body language expert told Insider Buttigieg was deferential to Harris on Tuesday in a joint Charlotte appearance.

• Meanwhile, Harris and Buttigieg's spouses spent time at a bagel shop, as documented on Chasten's Instagram.

Scott Rouse, a Nashville-based body language expert who has trained alongside members of the FBI, US Secret Service, and the Department of Defense, is in demand.

Typically, he spends his time appearing on "Dr. Phil" analyzing cases such as one of the last videos of Gabby Petito and her fiancé, Brian Laundrie, or advising US special forces at Fort Campbell on how to handle enemies and adversaries — "how to interrogate them and how to get an idea of what they will do next during personal interactions," he told me Tuesday afternoon.

All of which made him the perfect person to weigh in on Washington, DC's most scrutinized relationship of the moment: That of erstwhile 2020 Democratic presidential primary rivals Vice President Kamala Harris and Transportation Secretary Pete Buttigieg, who are now administration allies.

Video: Highlights from the Biden-Harris inauguration

That relationship came under the microscope again Thursday, as the duo embarked on a joint appearance to Charlotte, North Carolina, to sell the benefits of President Joe Biden's new $1.2 trillion-dollar infrastructure law, amid speculation that the two could square off in a 2024 primary should Biden, 79, not run for re-election. (Press Secretary Jen Psaki has said Biden's "intention" is to run again.)

It was one of their first big moments in public since Harris officiated Buttigieg's swearing-in ceremony back in February. Buttigieg helped her prepare for the vice presidential debate back in 2020, playing the role of his fellow Hoosier, Trump's vice president and former Indiana Gov. Mike Pence. Harris's husband, Doug Emhoff, has struck up a friendship with Buttigieg's husband, Chasten.

But throughout the Charlotte stop on Tuesday, Buttigieg, 39, the first openly-gay Senate-confirmed Cabinet official, went out of his way to be deferential to Harris. Buttigieg's advisers told Insider last month that he would be reluctant to challenge Harris, 57 — the first Black and first woman vice president, as well as the first person of South Asian descent to hold the office — and someone who has struck a genuine friendship with Buttigieg and his husband, Chasten — in a primary.

The duo toured a public transit facility at the Charlotte Area Transit System's bus garage Tuesday and made remarks about how the law will benefit North Carolinians. Meanwhile, Chasten posted an Instagram story with Doug Emhoff as they picked up bagels from Call Your Mother Deli back in DC. (In a bit of symmetry, Emhoff visited North Carolina with Pete Buttigieg to talk up infrastructure back in April).

To assess how the event unfolded, I asked Rouse to analyze several photos documenting Harris's and Buttigieg's interactions and their respective speeches.

For starters, the two embraced on the tarmac at Joint Base Andrews on Tuesday morning. Rouse said the hug was somewhat awkward. "Her feet are pointed toward him, whereas his are sort of spread a little bit," he told me. "But his left foot is pointing just a little bit away from her. When you want to focus on a person or a thing in a room, or in your surroundings, your feet will point toward that person. He seems a little bit ill at ease because he's back and he's leaning forward."

What's more, Rouse said, is the space between them. "If you really are happy to see someone, you're going to step right up to them and hug them and pull them toward you," he told me. "He's trying to make space from her where she's a little bit more into it than he is," he added.

Later, when the duo arrived at an all-electric bus depot and light rail garage, Harris sat in the driver's seat as Buttigieg looked on, his hand in his pocket, according to a vice presidential pool report.

"It's 2021," Buttigieg said, when asked by reporters as he briefed them alone without Harris on Air Force Two about whether he and Harris are mounting their own presidential campaigns (a person familiar told Insider Cabinet secretaries typically gaggle alone without the vice president on trips). "And the whole point of campaigns and elections is when they go well you get to govern. And we are squarely focused on the job at hand. I am excited to be part of a team led by the president and the vice president and I think the teamwork that got us to this point is really just beginning."

Did that mean the visit represented a united front with Harris, a reporter pressed?

"As transportation secretary, I get to be the face of a lot of these investments that we're doing, but we would not be here without the leadership of the vice president as well as the president; of course, and so many others," Buttigieg responded. "So I am glad we're able to shine a light on that today."

Later, in remarks before Harris's, Buttigieg praised and underscored the vice president's role in getting the infrastructure law across the finish line. "Her message was not to get lost in the details of the politics, but to remember the unique nature of the opportunity, he said about being in an Oval Office meeting prior to the law's passage. "She was exactly right. It helped shape the conversation."

Back inside the depot, Rouse told me he was struck again by Buttigieg's deference to Harris.

"Her eyes are wide open, see looking right at him, you can tell us he's not very comfortable in that seat," Rouse said. "She's kind of like a child there. But let's take a look at him. If you look, again, let's take a look at his feet. Neither one of his feet are pointing toward her once toward the door a little bit sort of anger toward the door."

"The main thing we're seeing here is his hand in his pocket," he added. "When you see someone with their hands in their pocket, and you don't see them, or their thumbs, that shows that they're they don't feel dominant in that situation."

A Democratic strategist interviewed by Insider said they did not expect that the joint appearance would put to rest talk of a possible Buttigieg-Harris rivalry.

"I don't think it's because of anything that did or didn't happen today. It's just generally speculation season," this person said. "To that end, Pete and Kamala both did what they needed to do: sell this historic infra[structure] law so that the American public knows which party's agenda to back ahead of midterms."

Read the original article on Business Insider