Institutional reforms and co-optation are critical strategies for political survival, enabling leaders to secure their dominance. While the co-optation of opposition elites has been extensively studied, its impact on broader society has received is less known. We argue that legal mobilization, through which political leaders seek to manage popular grievances into controlled arenas such as courts, can also be considered as a form of co-optation. This study leverages a unique national conjoint experiment in China to explore when citizens are more likely to resolve disputes with government agencies through administrative litigation. Our findings reveal that a dispute is more likely to be taken to court when the case involves a local and female plaintiff and is filed as a group case. However, none of these factors deters the use of courts when respondents are informed about reforms designed to improve citizens’ access to administrative litigation and, implicitly, their chances of success. Further analysis suggests that the pro-engagement effect of reforms is strongest among individuals who either have not heard of these reforms or have not been co-opted by the regime through party membership or state employment, suggesting a potential complementary Bayesian updating process. These findings expand the literature on the microfoundations of institutional co-optation in hybrid and authoritarian regimes.