When Does Similarity Count as Plagiarism? Judging Potential Norm Violations Through Publicly Visible Portfolios

ABSTRACT When the boundary between norm compliance and violation is interpretively ambiguous, how do observers evaluate particular acts? Why are similar behaviors deemed legitimate in some situations but criticized as transgressions in others? Prior research shows that norm‐violation judgments may reflect a focal actor's insider status inferred from prior interaction. Yet on digital platforms, observers increasingly encounter unfamiliar others whom they know primarily through publicly visible portfolios. How do they evaluate potential norm violations when person‐specific interactional knowledge is limited? Drawing on fieldwork with illustrators evaluating platform‐shared artworks, I propose a framework centered on portfolio‐identity consistency (PIC): the perceived consistency between publicly visible portfolio cues and expectations associated with a relevant social identity. Observers are more likely to classify potentially imitative works as plagiarism when PIC is difficult to construct, but as permissible referencing when it is readily constructed. In illustration, PIC is constructed through three interrelated cue domains: stylistic coherence, career trajectory, and sustained effort. The framework also explains illustrators' denunciation of AI‐generated art. More broadly, the study shows how observers use accumulated public outputs to construct insider status and interpret potential norm violations when interactional knowledge is limited.