From the moment he entered the courtroom for his long-awaited sentencing for the quadruple murders of four University of Idaho students, Bryan Kohberger projected what experts described as a cold, robotic presence. 

According to body language expert Susan Constantine, his frozen posture, sunken appearance, furrowed brows, and manic stare suggested a man attempting to control the courtroom with "covert hostility" masked as indifference.

His mask at times cracked in subtle ways as he was sentenced for the murders of Kaylee Goncalves, Ethan Chapin, Xana Kernodle and Madison Mogen and listened to the emotional victim impact statements.

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Constantine told Fox News Digital that his body language communicated "emotional detachment" as he sat rigid in an orange jumpsuit and shackled ankles listening "intently" throughout the multi-hour sentencing.

Body language expert and defense attorney Linda Kenney Baden described Kohberger as "an empty vessel filled with hate," telling Fox News Digital that despite his efforts to appear unbothered, his emotions at times betrayed him.

"Involuntary blinks, winces, breathing shifts, and occasional postural slumping," Baden said.

In one photo, Kohberger was seen shaking hands with one of his defense attorneys, Elissa Massoth, who is facing him. Kohberger’s expression is tense and composed, his lips pressed into a tight line as he maintains a fixed, forward gaze. 

Massoth, known for her work as a capital-qualified defense attorney, appeared professional and engaged at the moment, while Kohberger appeared rigid with his eyes piercing past her.

As victim impact statements kicked off Wednesday, his mask cracked in subtle but telling ways, like incessant blinking, leaning back, and tightened jaw movement, particularly when his ego was directly challenged by the families’ statements, Baden said.

Victim Statements:

Alivea Goncalves – Sister of Kaylee Goncalves

In Alivea’s victim impact statement, Constantine observed Kohberger’s "rapid blinking" following each emotional jab.

Kaylee’s older sister delivered a scathing rebuke of Kohberger, saying that he was "not profound. You’re pathetic."

Constantine said that Kohberger’s escalating blinking signaled "discomfort and ego disruption" as Alivea issued her "sharp and condiment tone with an edge of condescension and snarkiness towards Kohberger."

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Baden called Alivea’s statement the "star of the courtroom," saying that she had "rattled the snake’s head off."

Her takedown included rhetorical questions challenging his motive and intelligence.

"What were Kaylee’s last words?" she asked. "Do you feel anything at all—or are you exactly what you always feared? Nothing."

"You didn’t create devastation. You revealed it, and it’s in yourself," she said. "That darkness you carry, that emptiness, you’ll sit with it long after this is over. That is your sentence."

Kristi Goncalves – Mother of Kaylee Goncalves

As Kaylee’s mother expressed that Kohberger "stole her peace," Kohberger remained stone-faced.

"When you murdered my daughter, you shattered others. You stole my peace. You altered my every waking moment," she said.

Both Constantine and Baden pointed to Kohberger’s subtle shoulder tension and tightened jaw as Goncalves’ landed another emotional punch.

"I wish I could crown you with a jester hat," she said. "Go to hell."

Constantine and Baden said that Kaylee’s mother's sarcastic jab at his "genius" status and calling him a "joke" assaulted "his constructed self-image."

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Steve Goncalves – Father of Kaylee Goncalves

Kaylee’s father, Steve Goncalves, physically moved the podium to confront Kohberger eye-to-eye. It was a "direct power reversal," Constantine said.

"The world’s watching because of the kids, not because of you. Nobody cares about you," he said. "In time, you will be nothing but two initials, forgotten to the wind."

He called Kohberger a "joke" and described how easy it was to track him down.

"Police officers tell us within minutes they had your DNA. Like a calling card. You were that careless. That's foolish. That's stupid. Master’s degree? You’re a joke. Complete joke," he said.

As Goncalves "downgraded" Kohberger from criminal mastermind to sloppy coward, Kohberger leaned back, the only full-body reaction noted by Constantine.

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"His full-body reaction [to Steve’s statement] was indicative of discomfort, retreat or shock," she said.

Scott Laramie – Step-father of Madison Mogen

Laramie’s voice, though quieter, hit a nerve, Baden said. The body language expert noted that Kohberger winced and his "breathing changed" as Laramie spoke about Maddie.

Laramie said the tragic loss of their daughter has left a "vast emotional wound" that will "never heal."

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Jazzmin Kernodle – Sister of Xana Kernodle

Constantine noted Kohberger’s "emotional void" as Xana Kernodle’s older sister spoke, declaring: "Her light still shines, and her voice will echo louder than this pain. You didn’t take that from us. And you never will."

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Kim Kernodle – Aunt of Xana Kernodle

Baden noted a shift in posture as Xana Kernodle’s aunt offered an olive branch in forgiving Kohberger and offering to talk.

"For the first time, Kohberger slumped slightly, exposing his stomach chains, perhaps revealing fatigue discomfort, or unacknowledged remorse," Baden noted.

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Fox News Digita's Michael Ruiz contributed to this report.