Ghosts of the Civil Dead (1988) IMDb
A slightly futuristic Australian maximum-security prison. The inmates are initially able to maintain a good supply of normal stuff, plus drugs, but violence ends guard corruption, and privilege after privilege is suspended. The semblance of normality and freedom is lost. Demeaning searches, provocations, escalation of violence, total brutalization. Eventually there is little left but hate and death-wish among prisoners who have already lost their rights as citizens. Monologue narrators include one of the guards and an old man who was imprisoned for the first time at the age of 16. In the end, we hear the old man’s theory on why it happens.
Perfect clinical terror, partly by omission.