<p>Top-down environmental protection inspections have been conducted to promote sustainable development in many developing countries over the past decade. However, the magnitude and pattern of their impacts on carbon dioxide (CO₂) emission intensity have not been precisely investigated. By exploiting daily variations in CO₂ emissions with a generalized difference-in-differences strategy across 31 provinces and 1461&#xa0;days, this study discerns a clear temporal pattern for the CEPI effect on CO₂ emissions. In the two months before the onsite inspection, CO₂ emissions decreased by approximately 2.5%. During the one-month onsite inspection period, CO₂ emissions decreased by approximately 2.9%. This impact persists to a slight degree in the targeted area after the onsite inspection. The reduction effect is primarily attributed to the power and industry sectors, with an earlier manifestation in the northern area. The channels underlying this association are political-incentive-driven energy adjustment. Furthermore, this study identifies a similar impact pattern on the nighttime light levels, the effectiveness of certain enforcement measures associated with the CEPI, the slight response of CO₂ emissions in neighboring provinces during the CEPI, and strengthened positive spillover effects of CO₂ emissions across provinces after the CEPI. These findings shed light on the role of top-down environmental inspection in sustainable development and its potential limitations.</p>