If King Juan Carlos signs, what then?
That said, though, Human Life International seems to be over-reaching when they call, not simply on the king to refrain from signing such legislation (of course), but, in the event that the king does sign the measure, on the Spanish episcopal conference to declare the king excommunicated.
Two problems: first, it is not, repeat not, clear just what canon(s) HLI thinks put the king at risk for excommunication, but that's a discussion I'll reserve for those who are actually familiar with the relevant canons; second, and more to the point, not only have episcopal conferences no authority to declare anyone excommunicated, but, solely the Roman Pontiff may address canonical cases that involve "those who hold the highest civil office of a state" (1983 CIC 1405).
I hope, for the sake of his soul, that the king does not sign this measure, but, if he does sign it, the canonical consequences are not going to be decided by Spanish ecclesiastical officials. + + +
Friends tell me the king signed the act yesterday. Que lastima.