the 'non-criminal' often has no idea they've been found guilty of a non-crime. No investigation, no chance to defend yourself, no ability to appeal, no way to learn and amend your behaviour.
Amplifying this point because it's the nub of the issue.
No one is saying hateful speech is not bad. But this particular way of tackling it is also bad.
It's not ok to have secret blacklists, it's not ok to destroy someone's good name behind their back without giving them any chance to answer the accusations and it's not ok to do it based on one other person's subjective assessment or feelings.
Do it in the sunlight or don't do it at all.
Even this thread is a perfect illustration of the problem: someone immediately assumed the only reason anyone would object to the logging of NCHI by the police is because that person wants the freedom to be "racist/disablist/etc" without consequences and made that accusation. No time taken to understand what is actually being objected to and why before making the accusation, just a reflex reaction to trigger topics to make the "correct" response and label someone racist/disablist/etc.
Now imagine if instead of that playing out on MN where the misunderstanding could be challenged, it had resulted in a secret NCHI report where the accuser's misapprehension was taken as a fact.
(And all this is without even getting into the glaring injustice that sex, probably the characteristic that results in the highest number of people suffering non-crime hate simply because, with roughly half the population being female, there are so many women to suffer it, is not covered by NCHI.)