In this research, we investigate the citizen hijacking of the Twitter hashtag #myNYPD in response to a public relations campaign by the New York City Police Department in April of 2014. Using counterpublic sphere theory, we examine how Twitter was used as a platform to organize, generate, and promote counterpublic narratives about racial profiling, police misconduct and police violence. Through a combination of large-scale network analysis and qualitative discourse analysis, we detail emergent counterpublic structure and leadership, specific discursive strategies deployed by crowdsourced elites within communities of resistance, and the reception of online counterpublic activism in mainstream media. We conclude with implications for understanding the evolving nature of counterpublics in the second decade of the 21st-century, with particular consideration to the roles of new and old media in (re)shaping public debates around marginalization, profiling, and policing.