Susan Landau: Canaries in the Coal Mine [Huffington Post]

Mining mobile metadata

"Such transactional information is remarkably revelatory. A recent paper in Nature found that with 95 percent probability four location points were sufficient to identify an individual (home and work pairs are often unique). Location tells you lots: who is going to church on Sunday (and which church), whether someone has changed jobs, where they are going for medical treatment), and with whom they are spending their nights. Three decades ago, the last time our laws (specifically the Electronic Communications Privacy Act) codified government's access to telephone billing records, telephones were large objects that didn't go anywhere. Now, with the ubiquity of cell phones -- and the consequent disappearance of payphones -- everyone carries a device that reveals their location many times a day. This transactional information can be more revelatory than the content of the calls, which is currently much more highly protected by law."

Susan Landau: Canaries in the Coal Mine