We study perceptions of electoral integrity in Hungary using surveys and experimental data on over 4,000 poll workers that served during the 2022 general elections as observers and vote-counters. We first demonstrate that reports of irregularities were more common in areas prone to fraud, but were also shaped by the prior suspicion of poll workers suggesting that reports were partly driven by motivated reasoning. To rule out alternative explanations such as the selection of poll workers to ex-ante riskier areas, more vigilance exerted by more suspicious poll workers and “overinterpretation” of evidence driven by stereotypes, we fielded an experiment to the same poll workers where they evaluated hypothetical scenarios that were either perfectly legal, ambiguous, or unequivocally fraudulent Beliefs about fraud had a similar impact on perception as observing actual violations, questioning the reliability of survey-based measures of election fraud.