Foreign Intelligence Surveillance Act of 1978
“ In circumstances involving the unintentional acquisition by an electronic, mechanical, or other surveillance device of the contents of any radio communication, under circumstances in which a person has a reasonable expectation of privacy and a warrant would be required for law enforcement purposes, and if both the sender and all intended recipients are located within the United States, such contents shall be destroyed upon recognition, unless the Attorney General determines that the contents indicate a threat of death or serious bodily harm to any person. ”
