No, it is unlikely, even if remotely possible, that he will be detained for deportation in Chicago 'if this is a civil order of protection' in a different domestic relations court. Usually, the DHS does not attend such hearings at the Daley Center in Chicago, since there is usually no reason to do so.
If this is a criminal matter, then more information is needed, since if taken into custody for a crime, he can have trouble with ICE. There is also an understanding with Cook County Authorities that discourages such ICE activity in the civil and criminal courts, but ICE detentions and deportation can take place after processing in the Cook County Jail.
If your sister committed perjury, then your niece may have to decide whether to pursue action with the court. Your niece has the right to come to court, identify herself and try to have the restraining order lifted. If she takes no further action, and her mother does not go to court, the order may eventually end. However, more information is needed.
It is unclear whether your niece has done anything that may allow her ex to file for immigration relief. I strongly recommend an appointment for him with an experienced immigration attorney. Perhaps, there is hope, but more information is needed.
The above is general information and does not create an attorney client relationship.
There is always a possibility that court personnel or litigants in a civil suit will call ICE about someone unlawfully in the U.S. If he is picked up based on false accusations of abuse, he will need to consult with an experienced immigration defense attorney to determine what are his options.
Scott D. Pollock
Scott D. Pollock & Associates, P.C.
105 W. Madison, Suite 2200
Chicago, IL 60602
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