You should document your claim in writing to memorialize that you told her that you intended to claim the exemptions according to the decree, and that she is in violation of the court order. You could try to make a deal with her -- and memorialize that in writing too -- to take the exemptions for the next two years in compensation. If you both claim the kids, one of you, or the other, or both, may be audited. If you can't reach agreement, you could file a motion to either get the exemptions going forward, or seeking money compensation for the value of the exemptions wrongfully taken from you.
Answered on Jan 25th, 2017 at 6:42 AM