The heterogeneous impact of public security cameras on safety perceptions in cities: Evidence from China.

Digital public security systems in cities, such as surveillance cameras, can record illegal behavior and deter crime, thereby enhancing residents' perceptions of safety. However, the impact of public surveillance cameras on residents' safety perceptions in urban environments remains insufficiently understood, especially at the national level. Drawing on a novel dataset from Chinese government procurement records on surveillance cameras (2013-2017) and a representative national household survey, we find that a 10% increase in per capita camera expenditure results in a 0.2-unit increase in residents' perceived safety. Notably, this effect is observed only among local residents. For migrants, surveillance cameras improve perceived safety only when complemented by social ties, with neighborhood ties being more effective than distant ones in shaping these perceptions. Furthermore, the effectiveness of surveillance cameras on migrants' perceived safety is moderated by weather conditions and the inclusiveness of the urban environment. Our findings highlight that while public security technology can improve residents' safety perceptions, human-centered development remains essential for sustainable urban governance.