Prisons are not completely insulted from the happenings of everyday life outside in the real world
Inmates come from the real world and they bring with them a subculture typical of criminality and aggression
Includes a history of aggression norms meaning willing to use violence to settle disputes inside the prisons, Reflects life they had before entering prison
Aggression in prisons ultimately caused by aggressive characteristics of inmates carried 'in' from the outsides by prisoners no fault of the environment itself
Such inmates are predisposed to using violence ,would have done so in any setting, which is why they do the same in prison leading to institutional aggression