NOBODY outside of my home will hit my children - no matter what is offered for an excuse. That also applies to a school teacher who has not learned how to resolve the problem of a disruptive child, or may simply not be cut out for this profession. School is supposed to be a safe place for children.
As someone who attended Catholic school, I can attest to the fact that smacking children who do not comply to rules has the undesired effect of teaching those children to comply for the wrong reason - fear. They will learn to comply ONLY when a person of authority is present, not because they've learned the proper way to behave in society.
Many believe when the cycle of violence begins in a home by parents who use it to resolve issues with their children, the undesired result can be those children eventually land in therapy...or jail.