Do legal judgments influence people’s attitudes and beliefs concerning contested events? This article builds on studies from three disciplines – law, psychology, and political science – and employs experimental methods to shed light on the impact of legal institutions on their intended audiences. The article identifies a rising ‘legalization of truth’ phenomenon – the adoption of legal discourse to construct and interpret facts outside the courthouse. It argues that legal truth, while providing a framework of legal terminology and conventions to analyze and understand facts, comes with a price tag: it triggers cognitive and emotional biases that frustrate efforts to disseminate controversial information and to resolve factual disputes; and it lacks the emotional appeal, participatory value, and social cues that moral expressions or other types of social truth-telling entail.

To demonstrate the legalization of truth process and to measure its impact on attitudes and beliefs, this article focuses on the practice of international fact-finding. In recent years, international fact-finding has become a dominant response to armed conflicts and political violence around the world. Lacking compulsory jurisdiction, international fact-finding bodies have adopted legal discourse, assuming that legal reports uniformly inform the relevant publics with an authoritative account of what happened and motivate domestic sanctioning of in-group offenders.

This article challenges both assumptions. Based on two survey-experiments fielded in 2013 and 2014 on representative samples of 1,000 and 2,000 U.S. nationals, respectively, as well as on an original dataset of U.N. fact-finding missions, the study demonstrates that three elements of legal discourse – binary legal judgment, ‘hot’ legal terminology, and legal frame – harm the perceived credibility and persuasive value of fact-finding reports: the legal judgment of the fact-finding report is likely to trigger cognitive biases and belief polarization; ‘hot’ legal terminology is likely to trigger emotional biases and reduce the perceived fairness of the report; and the legal frame appears to be less effective than moral frame in influencing attitudes on accountability.

The article concludes that international and domestic organizations should rethink their current design and practice of fact-finding bodies, acknowledge the limitations of adopting a legal discourse to interpret facts, and recognize the questionable efficacy of legal fact-finding in influencing attitudes and beliefs. Accordingly, the goals, structures, and processes of fact-finding should be reorganized, matching goals with appropriate structures and processes. By revealing the impact of the legalization of truth on people’s beliefs and attitudes, this article creates a new framework to understand the failures and successes of legal fact-finding in particular and the practice and output of legal institutions more broadly.