From a 1982 Interview of Mike De Leon by Film Historian Agustin Sotto
AS: Where did you get the idea for the electric chair sequence?
MDL: The electric chair scene I got from a book entitled The Mind Manipulators (1978) by Alan Scheflin and Edward Opton, Jr. The book contained a description of the Milgram experiment, named after Stanley Milgram, a prominent American psychologist. The experiment demonstrated that people will obey authority even if the consequences are serious as long as someone would take responsibility for their actions.
In the Milgram experiment, a victim who is actually working with the experimenter is strapped to a chair while the respondents watch the interrogation. Each time the victim answers falsely, he is given an electric shock. The fake drama comes to a climax when the victim pretends to have a heart attack. But even then the respondents were unconcerned. Some went as far as criticizing such simple questions. You see, people will obey blindly as long as an authority figure is present. In this case, it was the experimenter himself.
I asked Doy del Mundo to include this scene, and he devised the idea of the son (Ricky Sandico) leaving the fraternity but being forced back into it by the father (Chito Ponce Enrile) to uphold the tradition of the fraternity in the family. The father was a founding father of the frat and couldn’t accept his son’s decision. In the movie, he becomes a symbol of authority.