npr:

It’s been only a year and a half since the social protest movement around police violence commonly referred to as Black Lives Matter emerged as a major political force.

Much of this movement’s momentum-building and organizing happened on Twitter, and a fascinating new study by media scholars Charlton McIlwain, Deen Freelon and Meredith Clark mapped out how it happened and who drove.

The researchers combed through Twitter data from June of 2014, just before the police killing of Eric Garner in New York City, through May of 2015, shortly after the protests over the police killing of Freddie Gray in Baltimore. From nearly 41 million tweets, 100,000 Web links and dozens of interviews, they were able to map out who led the conversations and how they were connected to each other.

They found six big “recurring communities” that consistently talked about police violence over the year in question.

Combing Through 41 Million Tweets To Show How #BlackLivesMatter Exploded