Bryan Kohberger might have finally confessed to the murders of four University of Idaho students, yet the reason behind his actions remains a mystery.

This week in court, the 28-year-old criminology PhD student admitted to the November 2022 stabbings of Ethan Chapin, 20, Kaylee Goncalves, 21, Xana Kernodle, 20, and Madison Mogen, 21.

However, specialists suggest that Kohberger’s impassive and composed demeanor provides an unsettling insight into a personality that is hard to categorize.

The Daily Mail spoke to three psychologists and criminologists who have examined the available footage, reports and public history of Kohberger. 

All say the emerging picture is of a man whose internal world was shaped by rejection, isolation, control — and possibly obsession. 

They say Kohberger doesn’t fit neatly into any of the typical mass murderer categories.

He wasn’t driven by ideology, delusion, or a personal vendetta, nor does the attack resemble a spontaneous outburst or targeted revenge. 

Instead, experts say his actions suggest a more complex blend of control, obsession, and thrill-seeking that defies traditional classification. 

What follows is their assessment of who Bryan Kohberger may be — and what could have driven him to commit one of the most horrifying mass killings in recent memory.

REJECTION BY WOMEN

A consistent theme in Kohberger’s background is his struggle to form meaningful relationships, particularly with women.

There are no reports of long-term partners or past girlfriends, and the only confirmed account is a Tinder date in 2015 in which Kohberger allegedly followed a woman back to her dorm and refused to leave, only leaving when she pretended to vomit.

‘That date is very, very revealing,’ said Dr Raj Persaud, a UK-based psychiatrist. ‘It suggests that he had difficulty taking relationships further than a first date’.

‘There is something about him and his character that means girls want nothing to do with him. There is some sort of creepiness.’

Dr Persaud believes this difficulty may have fostered deep resentment over time, particularly toward women. 

‘For most of us, what happens is that, if we get rejected, we might go away and work on our social skills so we can understand the rejection better and improve,’ he said.

‘But what you see with some people is that they become angry with girls when they are rejected and then believe girls are withholding something from them.’

This anger, he said, can simmer over time and eventually explode.

Kohberger went through a drastic weight loss transformation in high school — reportedly dropping 100lbs in a short span — which may also signal a young man desperate to reinvent himself. 

But peers said the change in appearance came with an aggressive edge, with reports that he began putting friends in headlocks and exhibiting controlling behavior. 

Though Kohberger also murdered a male student, Ethan Chapin, experts believe Chapin may not have been the intended target but was simply present at the wrong time. 

EROTOMANIA AND OBSESSION 

Another possibility is that Kohberger believed he had a special connection to one of the female victims — whether or not any relationship actually existed. 

Dr John Brady, a forensic psychologist with 25 years’ experience, believes Kohberger may have suffered from erotomania: defined as a delusional belief that someone is in love with you. 

‘This rejection situation [of women rejecting his advances] can tie into what is called erotomania,’ he told this website.

‘It is a kind of love gone bad situation, where an individual initially wants to pursue someone as a love object, but then something goes wrong.’

He said it could lead someone to act out aggressively. If the object of their emotions is seen as being unfaithful, he said, it could also trigger aggression.

Dr Brady noted that this kind of delusion has led to violence in other high-profile cases — including the 1989 murder of actress Rebecca Schaeffer by her stalker Robert John Bardo. 

While prosecutors say there is no confirmed link between Kohberger and the victims, the family of Goncalves has pointed to an Instagram account that they believe belonged to him, which had followed both Goncalves and Mogen and liked several of their posts.

This same account, which vanished shortly after Kohberger’s arrest in December 2022, had reportedly repeatedly messaged one of the victims two weeks before the attack with the phrase, ‘Hey, how are you?’. 

People magazine also reported that Kohberger had visited a restaurant in Moscow where Mogen and Kernodle worked at least twice before the attack, though the owners have denied this.

THE THRILL KILL 

Criminologist Dr Meghan Sacks offered another theory: Kohberger may have killed not out of anger or obsession, but curiosity. 

‘I think it is very possible that, when looking at the motive, this is what we call a ‘thrill kill’,’ she told the Daily Mail.

‘That is the worst kind because there is no motivation. I think he wanted to see what it felt like to see someone, to choose a target, and then see what it was like to kill them.’

Dr Sacks noted Kohberger’s academic background — studying criminal justice and criminology — and his apparent fascination with criminal minds. 

He had even posted a survey online asking ex-convicts about how they chose their victims and what emotions they felt during their crimes. 

‘I mean, he is a criminology major, and he had looked at certain case scenarios and some of the research he did coincided with this,’ Dr Sacks added.

She compared his psychological profile to that of Joanna Dennehy, a British serial killer who murdered three men in 2013 and later said she did it to ‘see how it would feel.’ 

So, who is Bryan Kohberger?

Experts agree: Kohberger is not easy to define. He is not the ‘typical’ mass killer.

He wasn’t visibly radicalized or acting on a known ideology. 

Instead, he seems to have operated from a mix of internal pressures: rejection, delusion, curiosity — and a desire for control.

Kohberger’s courtroom demeanor was also revealing. Though he showed no emotion during the plea hearing, he made deliberate choices — standing when he didn’t need to, maintaining fixed eye contact, and speaking clearly.

Experts believe this wasn’t the absence of emotion, but the presence of control.

‘Underneath all of this, is this cold detachment that still says to him that he is in control,’ said Dr Brady. ‘He’s going to spend the rest of his life in prison, and he still has this attitude of non-chalance, of just another day in his life.’

But the question that haunts this case remains unresolved: not just how Bryan Kohberger killed — but why.