Finally Over? But where is the Murderer?

The murder case involving Amanda Knox, a student at my University in Seattle, has been continually evolving and changing for the last four years. The exact timeline of events is stated clearly in this article: http://www.elmundo.es/elmundo/2011/10/04/internacional/1317724323.html in a Spanish newspaper called El Mundo. On November 1, 2007 a British student named Meredith Kercher was murdered in her Italian apartment where she was studying abroad with the Erasmus program. Amanda Knox, her American roommate claims to have been at her boyfriend’s house at the time of the murder, but later revised her story, after her boyfriend didn’t have the same alibi. Here is where the trouble lies and my questions begin. The problem with this case, and many other cases is that the story of the accused is highly suspicious and often controversial. Yet, this Monday, Amanda Knox and her boyfriend were freed and declared innocent. Now the case has no potential murderers or convincing stories about exactly what happened that night. Someone was murdered, but because there is no hard evidence against the suspicious accused, they were let go. One comment on this article states: “Do not know what to say… and that’s what the judge and jury must have thought so they have released: there is no evidence, and no evidence, no crime”.

Is there a fundamental flaw in a justice system that allows the only suspects for a case and suspects that have on more than one occasion changed and revised their story about where and what they were doing on the night of the murder go because there is no hard evidence?

The above question goes back to the case of Troy Davis who was executed a couple weeks ago. His case was one of the most publically debated cases in a long time. The problem people had with executing him was that though he had gone through numerous trials and it was beyond reasonable doubt that he was indeed guilty of the crime, there was not a lot of hard evidence. His case ended the opposite way of Knox’s. How much hard evidence is necessary to be legal and ethical in these cases?

Should there be a time limit or cap on the number of times a case can be reopened?