Employing loyal external appointees has been identified as a key strategy used by incumbents to gain control over the state bureaucracy. This phenomenon is known as politicization and has been associated with democratic backsliding. Frequently, career civil servants perceive these appointees as illegitimate outsiders, leaders whose main objective is to ensure political compliance rather than advance the organization’s mission. In this study, we explore how civil servants interpret the presence of outside leaders in their organizations in the context of politicization and how this influences their job attitudes and behaviors. We use a mixed methods exploratory sequential design to examine a recent case of politicization in environmental agencies in Brazil. First, we interviewed 25 civil servants who reported an environment of abuse, fear, disengagement, and alienation due to the actions of outside leaders. We identified silence (both defensive and acquiescent) as a key outcome of this process. We extended and confirmed these findings with a quantitative study using a new sample of 255 civil servants. This second study allowed us to test the relationship between the variables identified in the qualitative analysis. Our combined findings indicate that politicization may reduce the effectiveness and capability of public agencies not only because some external appointees lack competence or a commitment the organization’s mission (as suggested by previous studies), but also because their behaviors and decisions can have a significant negative impact on civil servants’ job attitudes and behaviors.