A married parent has the same legal access to their child as the other parent unless there is a court order stating otherwise. Whichever parent has the child in their physical presence has “custody” at that time. This can often turn into a tug of war between married parents until a court steps in and makes a custody ruling of some sort.
However, when parents are not married, the mother automatically has custody of the child absent a court order that states differently.
Usually the first step for an unmarried father is to establish paternity in a court of law. This can be done either with a DNA test or a voluntary acknowledgment by both parents in court under oath. While being named as the father on a child’s birth certificate indicates paternity, it does not automatically grant paternal or legal rights. Only a valid court order can grant such rights. However, once paternity has been established, a request for visitation or custody can then be made by the legal father.
In some cases, non-parents can also request custody of a child that is not their own by birth or adoption. These cases usually involve allegations of dependency and neglect against the legal parents and take place in a juvenile court.