The Catholic Marriage Manual, Random House

Page 165.
Person who believe that sufficient reasons exist to justify separation must request permission to do so from their Pastor. The pastor will refer the case to the judges of the marriage Court established by the diocese.

Page 166.
When civil divorce action is permitted. Church law states that Catholics may not start a civil divorce action with the intention of ending their marriage. As we have seen, a civil divorce or annulment cannot destroy the bonds of any valid marriage. In the eyes of the state, however, two persons remain married until the divorce decree is granted. Therefore it may sometimes be necessary for a Catholic to go through civil divorce proceedings in order to protect his legal rights. When the church annul a marriage and states that a true marriage never existed, for example, the parties must obtain a civil divorce in order to be free to remarry in accord with the laws of the state. In cases where the church permits a couple to separate, a wife may find it necessary to sue for divorce in order to force her husband to support her and the children.

Only a properly authorized representative of the bishop can grant permission to a Catholic to apply for a civil divorce. Church authorities require that the person involved fully understand that civil divorce cannot destroy a marriage bonds. Some diseases require that the applicant for divorce swear under oath before witnesses that he or she is initiating the action only for civil purposes.

A grave reason must exist before church authorities will approve a civil divorce application. For instance, the wife may require a court order to force her husband to contribute to her support in the form of alimony. A husband may need this protection against debts incurred by his wife.

Another requirement is that no element of scandal will be attached to the divorce action. The party to the proceedings must always make it plain, in discussing this action with friends, relatives or others, that it is taken solely for civil reasons. Catholics who obtained ecclesiastical permission to begin divorce proceedings must never give the impression to those either in or out of the faith that their action represents any departure from church teaching.