I just assumed that corporal punishment was illegal these days - just learned that it is legal for public schools in 19 states and private schools in 48.
Your second grade teacher is the exact reason why I wouldn't give that permission to a teacher or school. Reminds me of the movie/musical Matilda. You're right students should not be terrified of teachers.
This family was given the push they needed to leave that (awful IMO) school.