How can I tell if a restraining order has been lifted?

The Order of Protection and any Court activity related to it is a matter of public record. So, you can go to the court where she filed it and obtain documents and information regarding its' status. You can even view the Petition, so that you know what her allegations were. If it is still in place, you could call law enforcement and he is technically violating it. However, in my opinion, it is doubtful that law enforcement would pursue this matter, since she is the Plaintiff and willfully ignoring the Order. If law enforcement doesn't have her cooperation and the complaint is not coming from her, then I just do not see them taking any action. If you believe that this man is a danger or threat to your child, you should discuss this matter with the Mother and, depending on the severity of the situation, possibly take Court action to protect your son.