The recent spate of police violence stories has been credited to the proliferation of smartphone cameras uncovering examples of excessive force. What is missing from that equation is the role of social media. Being able to record the event is not enough. The death of Eric Garner serves as an example where video used as court evidence can still be inadequate for combatting violence. http://www.vox.com/2014/12/4/7337157/no-indictment-eric-garner
There is little impetus to change unless systematically corrupt behavior is exposed to public pressure and interest groups. Social media plays a critical role in disseminating evidence as well as ferment the beginning of activist movements and public inquiry.
Social media is often accused of being short term and practically ephemeral. That is true. The news cycle on traditional media platforms tend to worse. How many times is your local TV station going to show a clip of an obscure shooting? Once, twice, maybe a third time when the programmed is re-aired. Social media is not constrained to a single one sized fits all schedule. This allows to serve a much wider array of new stories and cover numerous niches. Stories are allowed to fester, ferment and perpetuate, and once ready become viral and persistent.
Also the interactive model of social media is far more conducive to promoting social justice movements. Traditional media is a one-way stream. One message is broadcasted out to everyone with little participation, feedback. That makes having a discussion that incorporates more than a couple dozens of people nearly impossible. Retweets, likes, comments, shares, replies engage people on an individual level. My giving someone a voice, even a small one, provides a sense of agency. The ability to participate removes a sense of powerlessness that breeds apathy. This makes social media a natural tool in building social efforts around the latest police shooting, over reach or egregious violation.