Hiding in Plain Sight: Pseudonymity and Participation in Legal Mobilization

How and when do people participate in sustained collective action via the courts? Previous research highlights group identity or resources and political opportunities but overlooks civil procedural rules’ effects beyond the courtroom. This article explores how rules regarding privacy shape individuals’ decisions about sustained participation. Fears of exposing one’s identity deter participation, especially in the context of public trials. Yet, a paired comparison of litigation by victims of hepatitis C-tainted blood products in Japan and Korea reveals that court-supervised privacy protections, which were available in Japan but not in Korea, facilitate plaintiffs’ participation inside and outside the courtroom. They ease plaintiff recruitment and enhance claimants’ credibility. Counterintuitively, they also let claimants strategically shed pseudonymity to send a costly signal about their commitment to the cause. Theorizing “pseudonymous participation” as an understudied mode of activism between full exposure and anonymity demonstrates that seemingly technical aspects of law have significant political consequences.