This is more up aPD's line of work, but there's probably not enough info you've given us to answer your questions. There are several threads in the General Residency forum addressing some of these issues as well. Bottom line is that legal action is a tough approach to go, time consuming and potentially costly. If there is any way to get a new position without suing, that would be best, but, every situation is different. An initial consult with a lawyer is not necessarily expensive though.