"[T]oday's CCTV technology turns police officers into supermen and -women with powers of observation that extends well beyond what can be seen by the naked eye.
High resolution that goes well beyond ordinary vision is a fact of life. Today's systems will allow operator to zoom in from over a 100 yards away to read and record the print on political flyers being distributed on public sidewalks. Technology available today includes night vision and systems, which can bring images in complete darkness up to daylight level.
The current technology also includes infra-red, high-sensitivity equipment, and systems operating outside the visible light spectrum. These include Forward Looking Infra-red Radar (FLIR) systems able to detect activity behind walls, and infra-red systems able to detect activities in darkness."
ACLU