Legal Question in Family Law in California

The first issue is whether or not you have a formal order scheduling custody and visitation time that he is violating. If not, you need to file for one immediately. If he keeps the child in Colorado for the jurisdictional period (six months in most states) Colorado my acquire jurisdiction. If you do have an order that he is violating by refusing to return the child, you need to file a proceeding in Colorado to have the California order adopted by the Colorado legal system. At that point, Colorado authorities should enforce the order, up to and including arresting the father.