I think Big Brother is a good idea. Everyone should have their fingerprints, retinas, biometrics and DNA information on file; not so they can be tracked at all times, but so they can be nailed if they commit a crime. Why not? In fact, children should have GPS tracking devices on them so they can be found even in rural areas. Alot of people go missing and are never found.

But more than that, most criminals leave no material evidence. Innocent until proven guilty is false. They are not criminals because the material evidence is convincing to non-witnesses; they are criminals because they behaved AS criminals. More evidence is needed to help victims of crimes such as harassment, bullying, gangsterism, corruption, discrimination, hatred, things that create victims but leave no evidence -- "It's their word against his" type of situation.