Beyond Verdicts: Explainable Fact-Checking via a Linguistically-Grounded Multi-Agent Framework

Abstract

Automated fact-checking systems still fall short of producing explanations that mirror the depth and structure of expert human reasoning. In this work, we propose a multi-agent framework that integrates five specialized linguistic agents covering polarization, linguistic style, argumentation, plausibility, and contextual framing with web-based evidence retrieval, synthesized by a supervisor agent into structured reports resembling professional fact-checking outputs. We evaluate the framework on a dataset of fact-checked Brazilian news through a classification benchmark and two further quantitative studies of explanation quality, addressing: (1) Do the generated reports elicit reader confidence comparable to reports written by professional fact-checkers? and (2) Which explanatory dimensions most influence reader confidence? The classification benchmark shows the framework performs competitively with strong baselines. A blinded within-subjects study with 95 participants, analyzed via Linear Mixed Models, shows that post-verification confidence reaches levels statistically indistinguishable from expert-written reports, with plausibility and analytical depth as the strongest predictors of confidence gain and depth being especially important for implausible claims. Complementary LLM-as-a-judge experiments corroborate these findings, showing the framework’s explanations are consistently preferred for depth, persuasion, and plausibility.