Biden had to get special permission to do this, so we know it was an act flaunting his contempt for Catholic teaching on marriage. What will be the repercussions from Cardinal Donald Wuerl (Archdiocese of Washington, D.C.) or Biden's Wilmington bishop, W. Francis Malooly? I'm not holding my breath. Several bishops have recommended in the past that Biden be banned from speaking in Catholic venues and abstain from Communion, but there's no evidence he's ever complied.
Canon lawyer, Ed Peters, says Biden's act is not an act that justifies excommunication, but it could be if the proper authorities take action:
No canon excommunicates a Catholic for officiating at a “same-sex wedding” but Pope Francis or (long story made short) Cardinal Wuerl could issue legislation making such officiating an excommunicable crime. Canon law has long responded to changing pastoral needs with new legislation, and this seems to be one more example of where new law might assist the Church in dealing with a new and grave problem.Amen to that, but do any of us expect the "hapless bench of bishops" in the United States to do anything to protect the flock from scandal. They are too busy justifying giving money "for the poor" they've defrauded from Catholics in the pews to so-called charities that support abortion and distribute condoms and teach explicit sex-ed to third world youth.
Don't you wish you could see how many U.S. bishops vote for the Clinton/Kaine ticket in November? Frankly, I'd be surprised if it isn't a majority.