The Pope IS the Pope. But he holds a LOT of views that are not Catholic. The just application of capital punishment has been a consistent Catholic teaching, if not itself any dogma. It's based on the very notion of Justice. Remember - this is the 'half-moon' Pope of Malachy's prophecy, friend to Islam and the UN. He's in no position to act as moral authority on anything, frankly. Not this Pope. Hopefully the next.
Well, I'm not a catholic myself. However, I am greatly amused that you believe yourself to be a greater authority on catholicism than the pope himself. I wonder what the Catholics on FR think about that?