What May Have Caused the Las Vegas Shooter to Kill? An Expert’s Analysis

Nearly two weeks later, investigators have yet to announce a potential motive behind the Las Vegas massacre, which killed 58 concertgoers and left hundreds more wounded. It may never be known what drove Stephen Paddock to shoot innocent people enjoying a country music festival from 32 stories up. But criminal profiler John Kelly tells PEOPLE he believes Paddock was born a killer.

“What would drive somebody that is so methodical and structured in life to go insane in a very structured and methodical way?” Kelly, who acknowledges he never met the shooter, wonders. “Paddock was a pathological gambler, psychopath and a sociopath. He was predisposed from birth and childhood to harbor extreme internalized shame, low self-esteem, depression, and aggressive anger.”

Kelly adds: “This was exacerbated with pathological gambling, Valium and alcohol that caused the perfect storm for mass murder: a delusional, psychotic illness which resulted in violent, suicidal, and explosive murderous rage.”

Kelly, a criminal profiler for nearly 20 years and the president of profiling team S.T.A.L.K. Inc., tells PEOPLE autopsy results released Wednesday did not uncover any brain abnormalities, such as a tumor.

“We have seen this play a role in a similar mass murder,” Kelly says, noting Charles Whitman, the “Texas Tower Sniper” who killed 17 on the University of Texas at Austin campus in 1966, had a tumor pressing up against the part of the brain that regulates anxiety.

The shooter, 64, targeted the Route 91 Harvest festival and began firing on the crowd from his hotel room at the Mandalay Bay Casino and Resort — directly across the street from the concert — shortly after 10 p.m., just moments after country star Jason Aldean took the stage for his show-closing set.

The former accountant took his own life. Authorities found his body surrounded by spent shell casings and piles of bullet-filled magazines. His car was recovered, and inside, police found explosives.

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“After eliminating any physical precursors to Mr. Paddock’s murderous rage, we would need to start to look at this individual’s beginning, which was in the womb,” Kelly says.

The shooter, he explains, was born the son of a convicted bank robber, Benjamin Paddock, who was once one of the most wanted men in the nation during the 1960s and ’70s and was “diagnosed psychopathic,” according to an FBI warning at the time.

“The strongest genetic connection of the psychopathic gene, the ‘Warrior gene,’ is transmitted from father to son,” Kelly explains. “This gene can cause extreme violence in an individual.”

Kelly says he has researched the shooter, learning he “grew up in an abusive, shame ridden and dysfunctional poor family. I believe that this had a traumatic effect on Mr. Paddock which started to cause him to have low self-esteem, depression, a sleep disorder, and internalized anger.”

In time, these dynamics “produced internalized rage within him,” Kelly posits. “This rage was destined to boil over and explode with murderous consequences.”

According to Kelly, “Mr. Paddock found gambling to be his ideal job and medication of choice.” Gambling, he tells PEOPLE, “is a central nervous system stimulant and, for a while, would be soothing to Mr. Paddock’s internal angst and trauma. However, over a long period of time, the frequency of gambling would have become a major stressor for Mr. Paddock.”

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Kelly also analyzed the shooter’s history of drug use, and speculated the killer was on Valium, a strong benzodiazepine and central nervous system depressant.

“Valium can have strong side effects, including agitation, paranoia, irritability, nightmares, rage, psychosis, hallucinations and delusions,” Kelly offers. “When mixed with alcohol, Valium can have even more complicated anger producing effects.”

Kelly also learned the shooter used .223 Remington rounds, which he says are “not designed to go straight through a person. This round has a devastating tumbling effect and will usually go in one part of the body and come out on another part.”

Hence, Kelly suspects “that many of the wounded were hit with a round that wounded or killed others.”

He even suspects the shooter had more murderous aspirations.

“He had a car filled with explosives,” Kelly says. “To me, that says if he did get out of that hotel room and did happen to get in that car, he would have gone out with a bigger burst of fury.”

Kelly is also intrigued by the shooter’s decision to attack concertgoers in Las Vegas.

“It is the same city where his father wanted to start a church,” Kelly says.