What happens if an illegal alien marries a legal resident or legal immigrant?

The illegal can get a green card after marriage. If they came into the country legally, and just over stayed there visit they can do that. If they came into the country illegally, then they might be better off leaving and going back home. Then they can get a fiance visa. They can then come back into the country and have 60 days to get married. This way it looks like they never broke the law or entered illegally in the first place. If they file for residency or green card while they are here illegally, they will most likely be deported and sent back home with little chance of filing papework to get back in, because now the US government knows the story. This way may cost more to go back home, but it's playing it safe. You risk not getting married if you file the I-103 i think the form is.

If caught after marriage, while still residing in the US illegally, The person is also liable for criminal charges of:

  1. Falsifying documents (Marriage licences state: Legally residing in...)
  2. Attempting to gain US Citizenship under false pretenses.