Speakers’ responsibility for evidential claims

People are vigilant toward the risk of misinformation and assess speakers’ trustworthiness to calibrate their trust accordingly. This assessment can target speakers’ epistemic commitments, conveyed through evidential claims. Speakers may take responsibility for the truth of a proposition by reporting first-hand evidence (“I saw that p ”) or defer responsibility by referring to second-hand evidence (“somebody told me that p ”). This pre-registered study experimentally investigates whether trust calibration is sensitive to the accuracy of these evidential claims. Our findings show that when a speaker shared accurate information p but provided an inaccurate evidential claim, the negative impact on perceived trustworthiness was greater for the strong perceptual evidential claim than the weak hearsay claim. These results provide new evidence that overcommitting by claiming direct visual evidence for information acquired second-hand is more reputationally damaging than appealing to hearsay despite having direct evidence. We discuss the implications for designing more trustworthy artificial agents.