Though it might be possible that we can interpret this "it" either way, I believe that any analysis that rules out the possibility of "it" referring to Mafia is wrong. Macmillan (BrE) clearly states that Mafia "can be followed by a singular or plural verb". Google Ngram and a quick googling also clearly show the favor toward the use of the Mafia is, both in eng_us and eng_gb corpuses. — Damkerng T. 7 mins ago
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous
Anonymous