Do to some personal issues my spouse was asked to resign several years ago from her employer. She was a union employee and given the choice to resign or be let go. In talking with HR, and her union rep, she was told that if she resigned she would not receive a negative reference for future employment purposes. Well several years have passed and she has the opportunity for full time employment once again. During the reference check process, they contacted her former supervisor and asked the reason for separation; she told them that she was forced to resign. Is this legal? We reside in the state of Michigan.