Thank you for trusting your question to JA today. I am a licensed attorney with over a decade of law practice and over 20 years of experience in the legal field. I’m happy to be of assistance.
DFAS will not calculate back payments. They will only begin paying from the date they have the decree and a request to initiate those payments, which either of you can do (her or you).
Now, the problem here though is that the court could order back payment. Technically speaking, you owe that money whether she set up DFAS payment or not. In fact, some people with marriages less than 10 years can't set up DFAS payments, but the retiree still owes those funds to the former spouse and has to pay them directly.
There is a 7 year statute of limitations on enforcing a judgment, which is what a divorce decree is, so if you were retired at the date of the divorce, then the statute of limitations is running. If just retired after, then it can be argued that the decree really didn't fully come into effect until you actually retired and she could argue that it runs from the date of retirement.
If she seeks back pay from the court, through a motion against you for contempt of court (for not honoring the decree), the court would grant that, plus interest and issue an order of garnishment. DFAS then would honor that order. They just aren't going to come to that judgment themselves, as they are not a court.
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