Catholic politicians who authorize abortion by voting for a law or constitutional amendment are guilty of a grave sin, are subject to excommunication for the sin of abortion (as accomplices, at least), and are forbidden to receive Communion under Canon 915, 916, and 1364.
The problem is that Bishops will not excommunicate these politicians, will not recognize their automatic excommunication, and will not instruct priests to refuse Communion to them. And any priest who does refuse Communion to a politician, is likely to be kicked out of his ministry. It is unfortunate that many Bishops are more administrator than Apostle.
Ronald L. Conte Jr.