From Inquisitorial to Adversarial: Using Legal Theory to Redesign Online Reporting Systems

Abstract

User reporting systems play a central role in how online communities address interpersonal conflict and harassment, especially in private spaces such as direct messages, voice chats, and end-to-end encrypted messaging. These settings complicate evidence collection for community moderators while heightening users' concerns about procedural justice and privacy. To examine these challenges, we draw on adversarial legal frameworks from offline judicial systems and apply them to community-level reporting systems, using Discord as a research site. We find that online community reporting systems often follow an inquisitorial model, in which moderators lead evidence collection and case development, rather than an adversarial model, which gives users greater control over how evidence is presented and contested. Although adversarial practices can strengthen procedural justice and protect privacy, they can also introduce new risks of abuse, underscoring the need for careful threat modeling. Building on this analysis, we present a design space for giving users greater control over the disclosure and authentication of evidence while accounting for the privacy constraints and technical affordances of online communities. We conclude by discussing how this design space can inform platform-level reporting systems and how cryptographic techniques may help reinforce these systems amid growing distrust in platforms.