That would create a complex regulations where everyone if fighting over what is "required for the role"

The better, faster and easier solution is a path to quick expungement, this also has the added bonus of offering people an incentive to no re-offend.

IMO once you have completed all active punishment (ie you are no longer on parole or probation) your record should be sealed.

>>If we're so concerned about employers hiring bad employees then state should instead build a centralised database of bad employees and their reason for termination at previous places of work

That would actually be illegal under most state laws as most State's have Anti-Black List laws to prohibit such lists from being created.