Unfortunately, prior to or during a divorce or custody action, one of the parents will sometimes relocate with the children to another state, often leaving without obtaining the permission of the other parent. Whether a parent leaves New Mexico for another state or the parent relocates to New Mexico with one of the children, the innocent parent needs to understand their rights, which largely are dependent upon which state's courts have jurisdiction over the children to the marriage or relationship.
Jurisdiction generally describes a court's power to decide a case or issue. A court cannot decide a case when it does not have jurisdiction over the people involved in that case and the subject matter of the case. State courts generally have the power to decide family law issues such as divorce, property division, child custody, and child support. It is important to remember that custody refers to more than just the physical location of the children and their visitation with the other parent, it includes decision-making power over issues such as where the children go to school, the children's religious practices, important medical decisions concerning the children, and even what extracurricular activities the children will participate in.
In New Mexico and most other states, the courts do not gain jurisdiction over the issue of child custody until the child has legally resided in the state for a period of six months or more. The phrase "legally resided" means that the child has not been brought to New Mexico or removed from New Mexico in violation of an existing Court Order or in violation of the other parent's rights. Thus, the second state to which the children have been relocated, whether it is New Mexico or another state will not have jurisdiction over the issue of child custody until the child has lived in the new state for six months. The state from which the children were removed will retain jurisdiction during this six month interim period.
In the absence of jurisdiction, any court actions filed in the new state should be dismissed for lack of jurisdiction. The only pleading you should file in the new State is a Motion to Dismiss for Lack of Jurisdiction. You should file no other pleadings and avoid asking the court for any other relief. Filing of other motions or enlisting the assistance of the Court in enforcing other matters may be construed as consent to the Court's jurisdiction. Unless this is your intention, then you need to be very careful in responding to any actions filed in the new state.