As you are probably aware, an Italian court has reinstated a verdict of Guilty on Amanda Knox and Raphael Sollecito. My guess is that Knox will be able to avoid being extradited to Italy, but Sollecito has already been taken in. This whole post is based upon the assumption that both Knox and Sollecito are completely innocent of the crime. From the reading I've done on the case (the Wikipedia page and a couple of pro-guilt and pro-innocence sites) this seems pretty obvious. To claim that their guilt is "beyond reasonable doubt" is stupid and, in view of the fact that it condemns them to a decade or more in prison, evil. In this post I am more interested in the motivations of various people than in rehashing the evidence.
First, there's the police. I have low prior expectations of the honesty and commitment to epistemic rationality of police in general (combination of a state license to use violence and a lack of accountability) and given the mire of corruption that is Italy, these expectations dip even lower. (There's an anarchist slogan that the state hates organised crime because it doesn't like having to face competition; in the case of the Sicilian Mafia, I would suggest that this is pretty literally true). Why are they pursuing a case against two clearly innocent people? Presumably because they have a theory and because changing your mind is difficult, often painful. People in general don't like to admit they are wrong, and the police are presumably more comfortable sending innocent people to prison than they are practising good epistemic hygiene.
What about the judges and lawyers involved in the case? Lawyers are another group who I would tend to be suspicious of, and this wouldn't be the first time that lawyers have taken advantage of a case to make vast amounts of money.
The judges are less obvious. This whole post is speculation, and given that I have limited knowledge of the Italian legal system I don't hold out much hope of being right in this particular guess.
The jury, I guess, are just subject to many of the common biases that affect us. I remember that, before I read about the actual evidence, I just blithely assumed that Knox was basically guilty. There are a whole load of pro-authority biases we tend to suffer from, and these would encourage the idea that "If the police say they're guilty, then I'm sure they must be guilty." At least part of the motivation for this assumption was that Kercher was British ("us") and Knox was American ("them"), and it's at least possible that some members of the jury hold anti-American sentiment similar to that which I used to hold. Overconfidence bias almost certainly plays a role; and then finally there is the determined campaign of character assassination to which Knox has been subjected.
Finally, what about Kircher's family? Her brother and sister were at the trial, and their lawyer described the re-conviction as "a victory for justice". It clearly isn't - indeed, it's a travesty of justice that Knox and Sollecito have been imprisoned. Their imprisonment does not bring Meredith back. I can understand the desire for revenge, but a) it's not a very healthy desire and b) Knox and Sollecito are innocent, so it's not revenge. It seems to me that Kircher's family, who must surely be familiar with the evidence, are morally reprehensible for endorsing the continued persecution of innocents. Perhaps not as reprehensible as any of the parties with actual power, but then again one shouldn't expect much good from police.
Is it reasonable to describe all of these people as morally reprehensible? I'll grant an exemption to the jury - most people (regardless of intelligence) have no idea how to weigh evidence and they are just people who have been forced into this. But otherwise, these are people who for the sake of not admitting that they were wrong are willing to subject two innocents to decades of imprisonment. And I believe we need to have more shaming of people who use their own poor methods of reasoning as an excuse to force their views on others.