If you were not aware that she was still legally married then you are considered a putative spouse. Your final Judgment or divorce decree should have that language in it somewhere. Take that Divorce decree to the immigration lawyer and ask them to re-view it again. Make sure there are no time limits for asking for reconsideration.
If she entered into a bigamous marriage with you, I am afraid that you are out of luck.
Mr. Shusterman's (former INS Trial Attorney, 1976-82) response to your question is general in nature, as not all the facts are known to him. You should retain an attorney experienced in immigration law to review all the facts in your case in order to receive advice specific to your case. Mr. Shusterman's statement above does not create an attorney/client relationship.
If your ex wife was married to another person at the time of your marriage then your marriage is not valid for immigration purposes. Did you remarry after you learned of her other marriage? What does the divorce decree say? You should consult with an immigration lawyer as soon as possible to avoid missing any appeal deadlines.
Gabriela M. Lopez, Esq.
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