> Still though, IR cameras by their nature are always-on and always transmitting data. In the case of near-IR night vision CCTV cameras in common use, yes. Th

> Still though, IR cameras by their nature are always-on and always transmitting data. In the case of near-IR night vision CCTV cameras in common use, yes. The case of Kyllo v. United States specifically involved very expensive long-wavelength thermal imagers that are not typically used in civilian CCTV applications [0]. Furthermore, federal agents specifically pointed a mobile camera at the house to see temperature changes behind the walls, which differs from a static always-on installation. [0] There are fixed thermal surveillance imagers (see http://www.flir.com/surveillance/display/?id=64664 http://www.flir.com/surveillance/display/?id=64664 for FLIR's latest), but they're typically used for military installation security. Unlike NIR cameras they require no external illumination, and are tuned to detect the black-body radiation naturally emitted by warm-blooded things.