Nearly three weeks after the Las Vegas shooting spree that left 58 concert-goers dead and hundreds more wounded, the murderer's motive is still a mystery to investigators.
President Trump has shared his theory that the wires in Stephen Paddock's brain were crossed.
Paddock’s girlfriend says his thrashing and moaning in bed at night might have been signs that he was mentally disturbed.
But doctors found no obvious "abnormalities" in his brain.
“He was sophisticated enough to strategize that event to get away with it,” says veteran San Diego prosecutor Wendy Patrick. “To choose a hotel where they knew him, and they didn’t raise an alarm that he brought ten pieces of luggage up to his room.”
Paddock's rampage lasted about nine minutes.
Investigators later began raising questions about timelines involving a security guard and another employee at the Mandalay Bay resort hotel.
By the time Paddock’s gunfire was unleashed, his girlfriend had already gone to the Philippines, where he had wired her $100,000.
That made her wonder whether he was breaking up with her after a four-year-relationship.
Patrick suggests that Paddock's motive might have been less a reflection of insanity than methodical planning--and execution--of a thrill-seeking massacre, ending in suicide by way of a handgun.
“It’s almost as if he was looking for some kind of a source of excitement that he wasn’t getting,” says Patrick. “There’s more to this guy that we yet know. And I’m convinced that we’re eventually going to learn enough to come up with a motive.”