Did I do something wrong?

Dr Edward Peters writes:

Well, since you asked, here's what's wrong with assisting at the invalid marriages of AWOL priests

Monsignor Robert Reardon, the Vicar General of the Archdiocese of Cardiff, is apparently slated to be the next bishop of Menevia in England. But there's a hitch; word is getting out that, in 1979, Reardon officially participated in the civil wedding of an AWOL priest (my term for a priest who abandons ministry without obtaining dispensation from the obligations of the clerical state, including celibacy).

Reardon apparently admits the deed, but adds "If someone can show me the church law I am supposed to have broken, I would be interested, but I'm not aware of it." Does the archdiocesan vicar general really not know what church laws would have been broken by such conduct?

Here's two for starters.