If your future husband came to the US with a visa, even if it has now expired. You can "fix" his papers once you get married. He will not have to go to Mexico for his green card interview. If this is done properly, he should get his green card before the end of the year 2013. Because, it does not appear that you are familiar with the process. I strongly suggest that you consult with an experienced immigration lawyer before you do anything.
Answered on May 02nd, 2013 at 3:46 PM