It has occurred to me that some people believe they are the authority of evidence for others, but it seems to me that authority lies with the individual. However I would agree that there are societal standards both formal and informal.
So my question is what are these standards?
Societal standards are just the product of individual standards.
The main individual standard for evidence is 'does this match my preconceived opinions?', the main standard for 'not evidence' is does this contradict my preconceived opinions'. Therefore these are the main societal standards too.
There may be specific domains (law, the sciences, etc.) in which different norms may apply at times or based on contexts, but ultimately we all have different standards for evidence that tells us we are wrong than that which tells us we are right.
The divergence between the 2 increases the more emotionally attached we are to our original belief. Very little divergence when we have no emotional investment, significant divergence when we our emotional attachment is high.
Some are better at 'self-correcting' than others, but nobody is flawless in this regard.