Expert: Edward Bode - 6/22/2009

Question
What exactly happens to a Catholic when he marries a Protestant in a Protestant ceremony? Is he automatically excommunicated? Is he considered truly married in the eyes of the Church? What?

Answer
If a Catholic marries a Protestant in a Protestant ceremony, in the general law of the Church that is an invalid marriage.  Although the Catholic is not excommunicated, there is matter for mortal sin. [After the ceremony, the couple could approach a local priest to valide the marriage.]
United States bishops have the authority to permit such a ceremony as a valid marriage, but that permission has to be obtained before the ceremony.
If your question refers to a particular person, then that Catholic should talk with a local priest -- hopefully before the ceremony or afterward if it has already taken place.  The Sacraments can be available.  The priest can also explain any further relevant details that might affect the situation.
Please excuse my delay in answering your question.
Best wishes, Sam.