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Interface: a journal for and about social movements

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Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.


Peace and Conflict Studies


Protest events are a hallmark of social movement tactics. Large crowds in public spaces send a clear message to those in authority. Consequently, estimating crowd size is important for clarifying how much support a particular movement has been able to garner. This is significant for policymakers and constructing public opinion alike. Efforts to accurately estimate crowd size are plagued with issues: the cost of renting aircraft (if done by air), the challenge of visibility and securing building access (if done by rooftops), and issues related to perspective and scale (if done on the ground). Airborne camera platforms like drones, balloons, and kites are geospatial affordances that open new opportunities to better estimate crowd size. In this article we adapt traditional aerial imaging techniques for deployment on an “unmanned aerial vehicle” (UAV, popularly drone) and apply the method to small (1,000) and large (30,000+) events. Ethical guidelines related to drone safety are advanced, questions related to privacy are raised, and we conclude with a discussion of what standards should guide new technologies if they are to be used for the public good.