The Washington Navy Yard video shows us the moments before Alexis unleashed terror in Building 197.
"He's driving to work, he doesn't look erratic,” said Banks as the video played out. “You see him walking in normally here. Now you see he has a sawed-off shotgun. He's hunting in the hallways, playing the hunter. It's kind of like a police role in a movie more than anything else."
The FBI released the surveillance video Wednesday, nine days after a rampage in which Alexis killed 12 and injured several others before police killed him.
Banks believes the FBI released the video, because they want to reassure the public that Alexis acted alone.
"It proves he was in there with the gun,” said Banks. “We don't see him shoot anybody, but the FBI wouldn't release that, because it's too gruesome for viewing and for the families directly affected."
The FBI claims the 34-year-old Navy reservist was delusional, believing that he was being controlled by electromagnetic waves. He had apparently scribbled messages on the side of his weapon indicating that belief.
The federal investigation has revealed that Alexis was prepared to die during the attack. Banks says with very little criminal history to go on, investigators will have to go back decades to really get to the root of what triggered the violence.
"I mean this could've started in his childhood and it culminated at an unfortunate time in his life and an unfortunate time for those who got injured and killed," said Banks.
Banks also suggested someone dropped the ball while vetting Alexis for a security clearance to do contract work.
Most likely investigators will shift their attention to that angle to try and fix what security measures obviously didn't work.