The question has arisen whether law enforcement agencies can or should refuse to recover minor children of an unmarried mother from a person (for example, from the biological father) who has no court order for custody. The answer is "No!" Law enforcement agencies should assist the unmarried mother of children who are wrongfully taken from her and kept by another--even if that other person is the father of the child(ren).
Section 6 of the Acknowledgment of Parentage Act gives a biological mother initial custody of a child without prejudice to the father's right to seek a court order for custody or parenting time. See MCL 722.1006 here. However, it is common for law enforcement agencies to refuse to assist in cases where, for example, a father may take the child(ren) and run, or may keep them from or hide them from the mother. "It's a civil matter," they will usually say. "You have to go to court to get a court order." Parents and lawyers should persist. In Michigan, Attorney General Mike Cox was asked to give a written opinion of MCL 722.1006 and his opinion is that the police may rely upon an acknowledgment of parentage if there is no custody order.
Attorney General Mike Cox wrote (in part):