@OCCOM BILL,
Well, I'm not a professional lawyer, so I don't exactly know the difference between American and Italian system, anyway, speaking just about concepts...
In Italy a prosecution for criminal facts starts with an accusation (in this matter the policy did it directly) then a judge must pronounce a sentence giving his "luogo a procedere" (permission to go ahead), it is not so immediate, because "luogo a procedere" imply the accused can be convicted in jail for a long period... then comes the "primo grado" (first grade) this is a complete process, we are at this point, now. The "primo grado" sentence is fully executive, but any part can appeal the sentence (for instance Kercher family could too, if they thought the sentence was too moderate for Amanda Knox) if an appeal is call then come the "secondo grado", this is a complite review of the process, new evidence can be exposed, as well as new interrogations, the outcome is not granted by any means, the judges and jury are different from "primo grado". Many process have been overthrown completely in "secondo grado", and the punishment can bee different too, (so for example, Amanda could be found again guilty and be assigned 10 years, instead of 26). Again an appeal could be called by any part. In that case there will be a third grade, pronounced by the "cassazione" court. In this third process the cassazione states about the "secondo grado" procedure, if circumstances and evidences have been valued correctly, if everything has been done according to the correct procedure and so on. Cassazione can ratify the sentence (that so became definitive and can not be opposed again) or can send it back to "secondo grado" with some indications (those indications intend to be significant for future interpretation of the law and so are very important)
That's about all, a long post for a very long procedure. It is so to grant that if someone is condamned, it is absolutely certainly guilty, accordind to the principle that "E' meglio assolvere 10 colpevoli che condannare un solo innocente" (it is better to absolve 10 criminals than to condemn a single innocent). Sadly it is not easy practically and so process very often last for many years before a definitive sentence is pronounced...