I was just informed of this situation that occurred somewhere by a co-worker, and was wondering what the legal ramifications are (U.S. Law). To be clear, the scenario is as follows:

   - I tell my boss I've been offered a position at another company.
   - My boss later comes to me with a counter offer of a raise, if I choose to stay with them
   - I accept the counter offer, and inform the other company that I have chosen to stay with my current employer
   - After a week, my boss then informs me that I'm being let go, and that this should serve as a lesson to not mess with him.

For the above scenario, regarding U.S. law, do I hold any legal grounds against this? What options would I have to defend myself (and my family) from being blatantly told that I was fired because I was willing to accept another offer without some other counter-offer from my current employer?

As for the chap this did happen to, I'm informed that he contacted the company who originally gave him the offer, and they were still willing to bring him on-board. So, yay (somewhat) happy ending to an otherwise terrifying situation.