Breaches of digital responsibility can have serious societal consequences. This paper examines how such breaches unfold in quasi-public organizations undergoing digitalization, using the British Post Office Horizon scandal—which led to devastating consequences for subpostmasters, their families, and society—as a case. Drawing on the tension perspective, we identify two key mechanisms: Digital Tension Catalysis and Digital Power Reconfiguration, which illustrate how digitalization transforms latent tensions into salient ones and reshapes power dynamics, resulting in breaches of digital responsibility. Our analysis spans institutional, behavioral, and technological dimensions, revealing a progression from dilemmas to dialectics to paradoxes. We develop a theoretical framework that offers insights into how digitalization can catalyze tensions and reconfigure powers in quasi-public organizations. This model contributes to the literature on digital responsibility and organizational tensions, while providing practitioners with a framework for anticipating and mitigating breaches in digital transformation.