Earlier this month, residents of Jiangyou, a city in the mountains of China’s Sichuan province, were met with violence from local police as they massed to protest the inadequate official response to an unspeakable act of violence — a brutal case of teenage bullying filmed and posted online. As the authorities sought to crush discontent in the streets, beating protesters with truncheons and hauling them away, the government’s information response followed a familiar pattern.