Contextualizing the Framing Effects of Policy Adoption: Interstate Competition and Autonomous Vehicle Discourse in the U.S.

Why do certain frames gain prominence while others become marginalized in public discourse about emerging technologies? Existing research shows that policy adoption serves as a powerful discursive signal that shapes how issues are interpreted. Yet prior work generally assumes that these framing effects unfold uniformly across jurisdictions. This paper argues instead that the discursive impact of policy adoption is contingent on the interjurisdictional landscape. Integrating insights from policy diffusion theory, I propose that interstate competitive pressure conditions how strongly policy adoption reshapes public discourse. To evaluate this argument, I analyze how autonomous vehicle (AV) policy adoption influences local media framing across U.S. states from 2012 to 2022. Using a dataset of 13,171 news articles, I classify economic, technological, and social/ethical frames with Sentence-BERT, a state-of-the-art semantic model, and estimate causal effects using a staggered difference-in-differences design. The results reveal stark contextual variation: in high-competition states, policy adoption increases economic framing while reducing social and ethical framing, whereas technological framing remains largely unchanged; by contrast, low-competition states exhibit minimal shifts across all frame types. These findings show that the framing effects of policy adoption are relational and context-dependent, advancing research on policy feedback, diffusion, and the politics of emerging technologies.