Will coming on B1-B2 that is already gotten work? Should the person declare to CBP they are coming to get married and leave? How to minimize the risks?
This is better suited for an immigration attorney. I've changed the practice area.
DISCLAIMER: Jack L. O'Connor III is a family/divorce attorney licensed in the State of Arizona. This answer is general information only. The information presented should not be construed as formal legal advice, nor as the formation of a lawyer/client relationship.
I believe that the person should be forthright with CBP. If the person is honest and can prove that he/she is coming to the US to get married but will promptly leave the US, the person should be admitted. If CBP decides to take a tough stance and deny entry, the person can apply for "withdrawal of application for admission", so the worst thing (as unpleasant as it is) is that the person has to take the next flight out. However, if the person is not forthright, and CBP finds out. CBP could accuse him/her of misrepresentation and remove the person, which carries a lifetime bar.
Please note that answers to questions are for general purposes only. They are not legal advice and do not establish an attorney-client relationship.
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