TikTok, Instagram, and the “Fourth Party”: The Impact of Technical Design on Personal Content Moderation

This article analyzes how platform design—not just content—shapes personal content moderation (PCM) on social media. Using dispute system design (DSD) theory and the “fourth party” framework, it compares TikTok and Instagram to show how reporting tools, interface architecture, and appeals processes structure user power, constrain participation, and influence safety outcomes. Although the platforms differ in transparency, tone, and regulatory posture, both embed design choices that limit users’ ability to report harm or seek meaningful redress. These findings demonstrate why emerging online safety laws must distinguish between design regulation and content regulation to remain compatible with First Amendment protections. The article concludes by proposing design-focused accountability measures and user-participation strategies to improve PCM systems and protect vulnerable users.