AHuxley (892839) writes The Sydney Morning Herald is reporting that Australian federal and state police are using a no warrant cell phone tower metadata access technique called a "tower dump". A "tower dump" provides the identity, activity and location of all cell phones that connect a cellphone tower(s) over time (an hour or two). The metadata from thousands of phones and numbers connected are then sorted. Australian law-enforcement agencies made 330,000 requests for metadata in 2012-13. AHuxley links to some U.S. views on the same kind of massive data grab: The Wall Street Journal says they caputure innocent users' data; the Chicago Police Department is being sued for information on its purchases of equipment associated with this kind of slurping; and the EFF asks whether warrant protection for users' data will be extended by voice-comm companies as it has been for ISPs. I wonder what people would think of an occasional "postal zone dump" employing the same kind of dragnet but for communications on paper.