When the fatal gunshot was fired at the college campus event in Utah where Charlie Kirk was assassinated, many in the crowd stood completely still. This is a moment that has sparked confusion, debate, and conspiracy theories.
Now, a forensic neuropsychologist has broken down exactly why that happened.
Derek Van Schaik, who shares psychological analysis with his 654,000 YouTube subscribers, said the reaction is a well-documented neurological response to trauma - and not the suspicious behavior some online have suggested.
The brain’s emergency shut-off
“Some eyewitnesses at the event described physically freezing,” Van Schaik explained in a recent video. “And if you notice, others in the crowd also froze for a second. Do you know why? Yes. This is a classic freeze response.”
The body can sometimes shut down or freeze in high-stress situations before deciding whether to run or fight. Van Schaik says this is deeply wired into human survival instincts.
“When we are in shock from a sudden or unexpected traumatic event, our bodies may freeze because we don't immediately know what to do in that new unexpected and uncertain situation,” he said. “Evolutionarily, this response helped us stay still… and possibly avoid being detected in a potentially dangerous situation.”
One attendee, whose account of the shooting was included in Van Schaik’s video, described the moment he realized something was wrong: “I hear this pop. It sounded like it was close. And out of the corner of my eye, I see Charlie go back. And so I start to head toward Charlie.
"And I see that the security guys are already there. So then I duck, thinking, ‘Okay, maybe there's other shots coming.’ I'm still on the phone. My daughter-in-law told me this. These were their first words out of my mouth. No, no, no, no, no.”
Van Schaik noted that reactions like this - freezing, ducking, or expressing shock - are all part of how the brain attempts to cope with a rapidly unfolding traumatic event.
Not everyone reacts the same way
Van Schaik also addressed the growing speculation that inaction could point to complicity.
“Sometimes conspiracy theories are built on the idea that if someone froze, they must have known something or were in on it,” he said. “In reality, the freeze response is an automatic survival reaction for many in some situations and is often a non-conscious choice.”
Everyone’s nervous system responds differently under pressure, he said - shaped by trauma history, temperament, genetics, and personal or professional experience.
“There’s a lot of variation in all of us due to differences in how our nervous system is physically wired, prior experiences, and our individual stress responses,” Van Schaik said. “Past trauma, temperament, genetics, and experience - whether law enforcement, military, healthcare - all influence pathways getting activated in that split second.”