Quote Originally Posted by Zandor
In the USA the Supreme Court has ruled the use of thermal imaging devices unconstitutional. Such heat sensing devices cannot be use to secure a search warrant for the interior of a private building.
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Not unconstitutional, but rather it cannot be conducted without a warrant, since such thermal imaging constitutes a "search" as defined in the Fourth Ammendment. This is the gist of the Supreme Court ruling to which you refer. See Kyllo vs. United States. The important things to remember here are that such imaging technologies cannot be used without a warrant, but once obtained, a warrant allows thermal scanning to be conducted and used as evidence.

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