According to the rules of Catholic Church, can a priest marry a couple (in order for the marriage to be recognized by the church) without having a civil ceremony; could he face legal ramifications from the church or the state?
Can. 1071 §1. Except in a case of necessity, a person is not to assist without the permission of the local ordinary at:
2/ a marriage which cannot be recognized or celebrated according to the norm of civil law;
Outside of danger of death, it is not licit for a priest to assist at a marriage if the couple is not able to civilly marry. Such a situation needs the local bishop’s permission in order to continue. The Church recognizes that civil government has the right to place reasonable limits and restrictions on marriage. Only when the civil law would produce an injustice would the local ordinary grant permission for a marriage that would be against civil law.