Exploring how independent directors view CSR inequality using a quasi-natural experiment

Purpose The purpose of this paper is to explore corporate social responsibility (CSR) inequality, which is the inequality across different CSR categories. Higher inequality suggests a less balanced CSR policy. To determine if CSR inequality is beneficial or harmful, this paper investigates how independent directors view CSR inequality, using an exogenous regulatory shock introduced by the passage of the Sarbanes–Oxley Act. Design/methodology/approach To draw causality, this study relies on a quasi-natural experiment based on an exogenous regulatory shock that forced certain firms to raise board independence. This approach is significantly less vulnerable to endogeneity and is much more likely to show a causal effect. The results using propensity score matching, principal component analysis and instrumental-variable analysis are confirmed. Findings The difference-in-difference estimates show that independent directors view CSR inequality unfavorably. Specifically, board independence diminishes CSR inequality by approximately 34%-43%. Because the empirical strategy is based on a quasi-natural experiment, the results are more likely to show causality. The results also imply that CSR inequality is a crucially important aspect of CSR. Originality/value Although a substantial volume of research has examined CSR, one vital aspect of CSR has been largely unexplored. Filling this void in the literature, the CSR inequality is investigated. The study is the first to explore how independent directors view CSR inequality using a quasi-natural experiment.