Central environmental protection inspection and green technology innovation: empirical analysis based on the mechanism and spatial spillover effects

In this study, the central environmental protection inspection (CEPI) policy is considered a quasi-natural experiment. Based on the data of 216 Chinese cities from 2008 to 2018, the influence of CEPI on green technology innovation (GTI) is empirically examined mainly using difference-in-differences (DIDs), propensity score matching DID and spatial DID methods. The results indicate that CEPI can effectively promote GTI. Regarding different types of GTI, CEPI mainly promoted utilitarian GTI. Regarding the mechanism, CEPI significantly promotes local GTI mainly through the increase of environmental protection expenditure and research and development investment. Considering the dynamic marginal effect, CEPI starts to significantly promote GTI in the second year after the policy implementation but exhibited no effects in the third year. The extended study shows that GTI effect of CEPI only occurs in small-medium cities and big cities. Furthermore, there is a certain beggar-thy-neighbor effect between inspected and uninspected cities. Finally, the spatial decomposition of CEPI effects shows that the inhibitory effect of CEPI on GTI mainly occurs in the neighboring uninspected cities, while CEPI has no evident inhibition on GTI in neighboring inspected cities.