No. If the decree requires it, let him know you will file a motion with the court - if you retain an attorney, you can get your attorney fees reimbursed under favorable "rule to show cause" verdict.
Generally the threat in and of itself is sufficient to clear things up. If all else fails, talk to an attorney in your area for specific guidance.
The Court, not the IRS, ordered this - so begin contempt proceedings. To do that, call your Divorce lawyer and she or he will call or write your ex to inform him that this violation is unacceptable and if he persists, will result in court action leading to contempt and payment by him of your attorney fees. That should get the return. If not one time through contempt proceedings should teach him not to try that again.
So far, this is free to you. Until you pay a fee, I am not your lawyer and you are not my client, so you take any free advice at your sole risk. I am licensed in IL, MO, TX and am a Reg. Pat. Atty. so advice in any other jurisdiction is general advice and should be confirmed with an attorney licensed in that jurisdiction.
If your Judgment for Dissolutuion states that your ex must give you his tax returns, then you have the right to take him back to court. The court can compll him to produce his returns and if found in indirect civil contempt of court, to pay your attorney's fees as well. Your should consult a family law attorney who practices in the court where you obtain your divorce.
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