This article presents a detailed ethnographic account of objective practice among professional fact checkers, reporters who specialize in assessing the truth of political claims. Some critics argue that political debate is inherently value-laden and defies objective fact checking; I offer an alternative view highlighting the practical epistemology revealed in the newswork routines and discourse of working fact checkers. Drawing links between core concepts in the sociology of science and journalism studies, this analysis highlights how in moments of institutional unsettlement, verification relies on factual coherence, rather than straightforward correspondence. To develop this argument, I anatomize a fact check produced as a participant observer with a major national fact-checking organization.