How come it's not public information to find out if someone is a child abuser?

How come it’s not public information to find out if someone has any Child Protective reports or convictions for neglect or abuse? I work in the field, for a government agency, and if we look up a child in the system (system that we use) but don’t have a case for, we can get arrested. We received an article about someone getting arrested for this – I don’t have the article any more but the Manager sent it to us as an example of why we should not look up names that we don’t have cases for.

Why is it that as a citizen, I cannot call the responsible public agency and give them the name of someone and find out if that person has a conviction? If someone wants to hire a babysitter, and the babysitter has a child welfare record, the person hiring the sitter has no rights to the information? It makes no sense that the abuser has rights to their privacy but the parent has no rights to find out if the person is a bad candidate for babysitter by having abuse or neglect cases.

(Babysitter was just an example, and needing a babysitter was a hypothetical example of why someone might need the info)