The term "grandparents rights" usually refers to a grandparents right to file suit for custody of or visitation with their grandchild or grandchildren. In the United States, these rights are not guaranteed by the Constitution, nor are they based in case law, the body of law that develops from customs and court decisions. Instead they have come into being through the passing of state statutes by state legislatures. After a statute is passed, court decisions involving the statute can affect the way the law is interpreted and administered (case law).
The idea of a grandparent's right to custody or visitation is a relatively new phenomenon, usually traced to the latter half of the twentieth century.
Suits for visitation rights may be filed when the parents have denied grandparents access to their grandchildren. Suits are more likely to succeed when the parent who is the child of the grandparent has died or when divorce or separation has fractured the family unit. Courts often uphold the right of an intact family to make decisions about visitation.
Suits for grandparent custody may be filed in a number of situations in which such custody could be considered in the best interest of the child. These situations include parental death, incarceration, mental illness or substance abuse, as well as child abuse or neglect.
In both situations, the grandparent's right is strengthened if the child has resided with the grandparent or if the grandparent has been the child's primary caretaker for an extended period of time.
Most statutes direct the courts to consider the best interests of the child, but the courts will also consider the rights of the parents to make decisions concerning the child. Legal advice should be sought by the grandparent in most cases involving a grandparent's right to visitation or custody.