This is how it works. There are all sorts of policies regarding cheating, including plagiarism. The administration will tell anyone that there are high standards.
But when an event of cheating occurs, there is a wink and a nod, and a soft hand must be applied. If the rules laid out in the student handbook are invoked, it is likely that the heavy hand will fall on the teacher, not the student. If one is a part time teacher, they probably will not be invited back. If one is a full time teacher, they've already learned the unspoken rules.