Most people realize that emails and other digital communications they once considered private can now become part of their permanent record. But even as they increasingly use apps that understand what they say, most people don’t realize that the words they speak are not so private anymore, either. Top-secret documents from the archive of former NSA contractor Edward Snowden show the National Security Agency can now automatically recognize the content within phone calls by creating rough transcripts and phonetic representations that can be easily searched and stored. The documents show NSA analysts celebrating the development of what they called “Google for Voice” nearly a decade ago.

Though perfect transcription of natural conversation apparently remains the Intelligence Community’s “holy grail,” the Snowden documents describe extensive use of keyword searching as well as computer programs designed to analyze and “extract” the content of voice conversations, and even use sophisticated algorithms to flag conversations of interest. The documents include vivid examples of the use of speech recognition in war zones like Iraq and Afghanistan, as well as in Latin America. But they leave unclear exactly how widely the spy agency uses this ability, particularly in programs that pick up considerable amounts of conversations that include people who live in or are citizens of the United States. MORE