Surveillance video from the scene shows Mancilla using his S.U.V. to block Victor Cedano, then loading his gun.
Mancilla testified this week that he felt threatened and fired his gun in self defense.
The prosecutor said Thursday, Mancilla had plenty of opportunities to leave and accused him of lying.
Mancilla's attorney used another surveillance video showing Mancilla playing with his kids inside the restaurant and claimed his client had no intention of killing anybody that day.