Some people are just toxic and should be avoided.

But what do you do when they are your students and you have to teach them?

A student lied to me. Which is bad enough. Kind of a warning that this is someone to avoid, to not sully your personal space with. But I could teach that person.

Then the student lied about another teacher. A lie so egregious that, if believed, could cause the teacher a lot of trouble. I guess the good news is - the student has lied to many and therefore is not believed.

Still causes problems for the teacher.