The short answer? Yes.
There is no law to prevent an illegal or undocumented immigrant from marrying a US citizen. Most of the laws around marriage in the United States have to do with age ( legal consent ranges from 15-17 in most states with parental consent, and is 18-21 without it), and relationship status ( 1st cousins are Ok, in many states, but no siblings including half siblings).
SO AN UNDOCUMENTED (ILLEGAL) IMMIGRANT CAN MARRY A US CITIZEN, BUT WILL THAT GUARANTEE THEM A GREEN CARD?
Short answer? No
There have been many changes over the years regarding undocumented or illegal immigrants who married within the US to a citizen. Back in the day you could go ahead and get your green card after marriage, once you had paid a fine. Then in 2001 that part of the law was removed, and it was VERY HARD to get your green card after you had already been married. Then in 2013 that all changed with the 601 a Waiver. This waiver made it possible for many people to once again apply for their green cards through marriage on the grounds of extreme hardship to their US spouses.
A huge amendment to this waiver just happened in August 2016 that allows many more people to apply for their green cards with the 601 a waiver. These changes mean that more people than ever will be able to keep their families together!
SO NOW CAN AN ILLEGAL IMMIGRANT MARRY A US CITIZEN AND GET A GREEN CARD?
Short answer? Maybe
It is easier than ever to get a green card through marriage in the US, but with US immigration there are never any guarantees. With the new changes there are now no time restrictions on who can apply, there are less qualifications than before, and even if you have already received your final notice of removal you can still apply.
THERE HAS NEVER BEEN A BETTER TIME TO TRY AND BECOME A LEGAL US CITIZEN THAN RIGHT NOW!
If you have any questions about this or any other immigration related questions please do not hesitate to contact us at Harlan York & Associates.