Possible victim of marriage fraud

[santiago1989]

Hello everyone. I am trying to find some answers for a possible marriage fraud that someone I know of maybe a victim of. Here's the full story:
My friend (Mary) who lives in another country , married an American (John) after meeting him through an online marriage website. They eventually got married, after dating for several months, and he visited her in her home country to marry her and visited her several times afterwards. Recently, I have received a phone call from a person who lives where he lives, and told us that he is already married to the sister of the person that called me. As proof, the mysterious person also sent us photographs of the person he is supposedly married to. We have no proof of marriage between him and the other person. It is obvious that he has had a relationship with this person, but we don't know if he is truly legally married, or if this is a vindictive ex. John (the husband/supposed already married guy) has already applied for Mary's spouse visa, and currently it is at the DS-260 phase, where he needs to send in documents. So far he has followed through on the process on bringing her here, but we have reason to believe he maybe a fraud, since he has lied about several things previously, and also mentioned that he never dated anyone (as is custom in our culture). Because I do not know who to trust between the mysterious person and John, I am currently just going to let the situation play out without raising any alarm (Mary is unaware of this) and see where it leads. My fear is if I speak to the mysterious person again, she might use my conversation with her to stop him from bringing Mary here, in which case, it would ruin her chance of legally pursuing him if he truly did behave fraudulently.
I wish to know is it possible to actually file for a spouse visa if you are legally married in the USA. I know that he can get married in a different country easily if he is married in the USA, but can he actually bring a second wife. Wouldn't he have been stopped at some step during the visa process because of his marriage? I need to know how far he can go in the visa procedure before being caught, because only then will I know whether this mysterious person is speaking the truth or not. I just want to discretely gather as much information I can to make sure that Mary isn't screwed over by him if God forbid he is actually married. If anyone has any information regarding how the state dept. or homeland security actually verifies if someone is actually married, or how far John can go before he gets caught, I would be very grateful. This is an urgent issue. Thank you to everyone in advance.

[PryncissQueen]

Marriage/Divorce records are public records. You can search in the courts of his state/county

[jayleno]

I think they rely based on the information you give to them. But if they have any reason to doubt the information you provided, then they will go an extra mile to do their investigation. If I were you, just like you said to keep calm and watch out how everything plays out. I also believe it is an issue of an aggrieved ex who is yet to move on with her life. So why didn't they send you a picture of the their marriage or even a copy of their marriage certificate?

[santiago1989]

Thank you for the information about the search for marriage license. He currently lives in Maryland where you can look up marriage records online, but according to the person who called me, they might have met and married in Oregon, and I can't seem to be able to access any information through their website, I just might have to call. The mysterious person also sent me a criminal case that has been filed against him for assault, and he has a summons for that and is being prosecuted by the state. So I have enough reason to believe that there's more to it than just a vindictive ex. I'll have to check if it is possible to check background information about a defendant from the court. Unless someone has some better idea.