Has central environmental protection inspection improved air quality? Evidence from 291 Chinese cities

In recent years, central environmental protection inspection (CEPI) has been a major policy innovation in the field of Chinese environmental governance. Based on panel data on the daily air quality of Chinese cities, this paper mainly uses a difference-in-differences (DID) approach to conduct an empirical analysis of the relationship between CEPI and the air quality governance performance of Chinese local governments. There are large differences in the impact of CEPI on different air quality indicators. Controlling for a series of variables, we found that CEPI significantly reduced the air quality index (AQI) and concentrations of pollutants including PM_2.5, PM₁₀, SO₂ and NO₂ and that it significantly increased the concentration of O₃; however, it had no significant effect on the concentration of CO. Furthermore, we complemented the quantitative analyses with qualitative evidence gathered from an in-depth interview. Based on the qualitative evidence collected, CEPI indeed plays a role in improving the environmental protection performance of regular environmental governance. Notably, CEPI achieved better and sustainable results in improving air quality through the underlying mechanism of promoting regular governance by campaign-oriented governance in the internal hierarchical system. This article not only provides a marginal empirical contribution by providing new quantitative evidence but also helps reveal the underlying mechanism of promoting regular governance.