Doing an audit on Angels & Demons, and in the credits there are listed 4 actors under the role Carabinieri. I don't use dividers for those, I just enter the 4 names and the role after each one. But is it correct to use "Carabinieri" after each of them or should it be Carabinier grammar wise?

When I contributed the Finnish BD-version a while back, I had to check this exact same thing... as weio says, Carabiniere is correct (singular form of Carabinieri)

http://mw1.merriam-webster.com/dictionary/carabiniere