Warrant Requirement for Police to Use Advanced Imaging Technology

The Supreme Court has ruled that the use by police of a thermal imaging device to detect patterns of heat coming from private homes is a search that requires a warrant.

The warrant requirement applies not only to the relatively crude device at issue in this case, but to any more sophisticated systems that may already be in use or in development. Knowledge of this nature would have been impossible prior to these developments without physically entering a home.

This decision overturned a ruling by the 9th US Circuit Court of Appeals, in San Francisco which held in 1999 that the warrantless use of a heat detecting device revealing patterns that suggested indoor marijuana growing did not violate the Fourth Amendment's prohibition of unreasonable searches.