OP mentioned one error and the resulting policies because of it, I didn't see any others he mentioned. I don't think it's reasonable to know how many policies are determined based on sound data and processes, and how many are so politically motivated that nobody ever checks the numbers. You really only find out by happenstance when someone checks on a lark. We could make a concerted effort to verify everything, but where would you even begin for policies that have already existed for decades?