I understand your point, and I guess it's theoretically possible, but the Church has limited earthly powers.
I recently learned that the Catholic Church, with over 1 billion members worldwide, has an annual operating budget that is 1/3 of the operating budget of the University of Notre Dame.
It's not the federal government. Its resources for self-policing are limited.
Practically speaking, the buck stops with the local bishop.
http://www.trosch.org/exc/excommunicated.html
Excommunicated according to the 1983 Code of Canon Law:
Daschle’s (D., S.D.), Senator Tom
Ferraro, Geraldin — former V.P. candidate
Giuliani, Rudolph William Louis “Rudy” Giuliani III — Mayor NYC
Kennedy, Senator Ted
Pelosi, Representative Nancy — U. S. Speaker of the House, 2007 A.D.
Wuerl, Archbishop Donald (Cardinal) Washington, DC
Catholic Democrats from Iowa City and Dubuque that voted to human clone.
Sen. Bolkcom
Sen. Connolly
Sen. Dvorsky
Murphy
Jochum
Mascher
Jacoby per Michelle Locher
Quirk, Brian State Representative (D-New Hampton, MI.)
Now if you want to get real interesting there is a standing order of excommunication for all communists. Also understand that there are Canon Law violations that get automatic excommunication of which Nancy Pelosi and Sebelius are not in direct conflict with. No Bishop/Pope needs to make a formal pronouncement.