I had an interesting situation with a dealer this past spring...
I found out that one of my students was a dealer. This really tore me up inside, not only b/c I was having a really hard time with ras at the time, but also because I was developing such a bond with him (he was actually working in my class... not so for his other teachers- he made a B in my room and failed everything else, but he earned his B with flying colors). I am so thankful that nothing of that nature ever came up during my class... that is one of those things they don't prepare teachers to handle...