Looney has previously sought to portray Zamora as a family man and former youth baseball coach who lived in a simple home across the street from his parents.
The Perez slaying went unsolved until years later, when authorities investigating a suspected weapons trafficker caught a break.
In a bid for leniency, officials said, the weapons trafficker turned informant and led authorities into the middle of the rivalry between Zamora and Santiago Salinas, a hated rival.
Hit men allegedly working for Zamora shot Perez when they mistook him for Salinas, who looked similar, had a wife by the same name, and was even in the Chilos restaurant during the attack.