Do you believe that the deviant behaviors of the underclass are a product of a dysfunctional culture or external forces?

I strongly believe that is a combination of both.

Explanation:

External forces only exist because of the culture, and if the culture is dysfunctional, evidently we'll witness deviant behaviors. A culture that praises for consumerism, to overthrow traditional values such care, respect and regard of the family can only lead to deviant behavior, once young people and the general people as well, don't have any reference, because these references were destroyed. So, they try to create their references based on what they see or consider important.