I don’t remember many specifics…for smoking/drinking mostly just meet with the Dean and get told not to do it again. My D’s school had a 3x limit then more onerous consequences would kick in (but I don’t know what they were). Some academic misconduct suspensions and expulsions.
The most consequential, controversial and divisive issues were during covid…where kids breaking the ‘rules’ were sent home (allowed to study remotely) and seniors not allowed to walk in graduation.