If we observe experts changing their beliefs based on evidence often, but evidence changing based on the beliefs of experts never, then it seems reasonable that the chain of causality goes reality->evidence->beliefs of experts->beliefs of non-experts, with the possible shortcut reality->evidence->beliefs of non-experts, when the evidence is particularly abundant or clear.
If we observe experts changing their beliefs based on evidence often, but evidence changing based on the beliefs of experts never, then it seems reasonable that the chain of causality goes reality->evidence->beliefs of experts->beliefs of non-experts, with the possible shortcut reality->evidence->beliefs of non-experts, when the evidence is particularly abundant or clear.