I'm not sure about him really being a psychopath. He killed a lot of people, but that doesn't necessarily have to make you a psychopath. Most of the murders he commited were ordered I believe.

Another example is Toto Riina. He probably ordered more murders than anyone else in the history of the mafia. But this guy was a master in shaping alliances with others which suggest he knew how to deal with people, something most psychopaths have trouble with.

It's likely these guys were psychopaths, but I'm not convinced.