I first heard about a tragedy in Tucson, not from major television news networks, but from a direct message sent by a politically-active friend who was attending the political gathering where a mass shooting took place, including the shooting of an Arizona congresswoman, Gabrielle Giffords. While the television news sputtered around trying to offer details (initially wrongly claiming that she was dead, likely from pressure to be the first to report big news), I found myself reading Google News, piecing together Facebook posts, e-mailing friends and reading Twitter updates.
Spencer, John, "Technology Criticism in the Classroom (Chapter in The Nature of Technology)" (2013). Faculty Publications - School of Education. 236.