The same thing that's wrong with any unilateral arbitrary application of punishment - the presumption of guilt. This is kind of opposite to the founding fathers' ideas, but just in line with what government today wants.
You mean you never got hauled off to the vice principal’s office for a paddling in high school?
Yeah, I didn’t either, but I was well-behaved enough as a result of home life that it wasn’t necessary. But it did used to occur at the two high schools I attended, there was not generally a municipal court involved, and those who received it seemed generally deserving. And schools were more orderly then.
The real issue is that we don’t kick people out of school for misbehavior, as the money per student per day from state and Federal sources is too lucrative to allow it. Plus you get SJW types like the SPLC involved if you do it.
The overall result is disorderly schools where not a lot of learning happens. The real victims are those who came to learn, and not party, socialize, and smart off to teachers.
Do I understand correctly that you don’t believe that spanking should be an option?