Sure, he can ask the court for custody. That does not mean he will win. If he does file for custody, the best thing for you to do is to contact local, experienced family law attorneys. If money is an issue, you could see if legal aid or any law school clinics in your area would help you.
Best of luck.
Attorney Inga Stevens is licensed in Maine. She provides general information on Avvo.com. No attorney-client relationship arises out of the information given here.
The short answer is, "yes", he can always try to fight for custody and/or visitation. Remember, anyone can pretty much file anything they want in court. That being said, winning is a whole different story. These cases are fact driven and depend on a number of factors--the most important being the "best interest of the child." Courts rely solely on what is in the best interest of the child in determining a change in custody and/or visitation. That being said, the standard for modifying either is different if there is already a judgment in place. If so, then the moving party (dad) needs to show a significant change in circumstances that deems it necessary for the change to meet the best interests of the child. If the order is not permanant, then dad can try to increase custody/visitation by filing and order to show cause for modification and simply asking for it. However the facts will determine if he has any chance. Specifically, if he has a history of drug and alcohol arrests and continues in the same life pattern, then he probably will not have much of a chance. However, as I said, this is a fact driven analysis on a case by case basis. The issues of citizenship, taxes, and living with his sick mother probably will not be relevant unless his mother home is an unsafe and/or inappropriate environment for a child. To be sure, there are many other factors that must be analyzed to address this issue properly. If you have any questions, please do not hesitate to contact me directly at 909-635-2023.