Well, some thinks were based in the fear of the time, and other are completely different. For instance, the precogs were deformed mutants with latent abilities; Anderton was the Police Chief and was close to retirement, and Witver was his young second-in-command; Anderton's victim is a completely different person; the precogs know the other's predictions and knowing them affect their own predictions and the future; Anderton's crime is justified, and when he's encarcerated, Witver takes his position and wonders if he will be forced to make a similar decision in the future.