So, let’s take the occasion of Amanda Knox’s return to Italy to tell a different story based on the same evidence. This is the most important exercise in dealing with circumstantial evidence, which is great if it has only one plausible explanation, and worthless if it has more than one.  We recall seeing one of those lawyer type movies about just such an exercise at some point in our youth.

We begin with the notion of the “alibi” defense.  We have noted previously that alibis are an extremely dangerous defense to offer, because if they are not ironclad, an inference will typically be drawn that not only is the propounder wrong about where they were and when, but has actually been deliberately deceptive about it, which in turn is seen as an admission of guilt.

So, back when we were writing about this matter – because current at the time – someone suggested that Meredith Kercher’s boyfriend had been ruled out early on by the police – owing to an alibi – but that the alibi was not ironclad. We don’t know one way or the other, and of course we are hypothesizing only, but if we start from the proposition that his alibi was no good we can tentatively infer deceptiveness and even guilt, and go on to construct the following narrative.

Everyone is away from the Perugia flat for the holiday except for Meredith and Amanda, but Amanda has been spending her time at her boyfriend’s leaving Meredith alone, with the flat all to herself. Meredith’s boyfriend is supposed to be out of town, too, but he decides to return and surprise Meredith. Unfortunately, this leads him to discover that Meredith is having an encounter with Rudy Guede.  He watches the whole episode from outside, feeling increasingly angry and betrayed. When he sees Guede leave he enters the flat to confront Meredith, there is a violent struggle that spills over into Filomena’s room when Meredith attempts to flee, the boyfriend winds up killing Meredith and then he leaves.

In fact, however, Guede had not left the flat, he had only left Meredith’s room to use the bathroom.  Frightened by the commotion he heard, he waited in the bathroom until it stopped and the flat was again silent.  He then exits and goes back to Meredith’s room where he finds her dead.  He is traumatized and ashamed that he remained hidden and didn’t do anything to help her, he worries that people will think he did it, that there is evidence on her cell phone(s) connecting him to the crime.

So he covers her body with a duvet, goes back to the bathroom to check his appearance in the mirror, goes back to Meredith’s room to retrieve his shoes, takes Meredith’s cell phones and keys and some money.  When he looks at the shoes he sees blood on the right one so he leaves that one off, puts on the left shoe, walks out of the flat before putting on the other shoe.  Of course there was blood on the left shoe, too, he just didn’t see it. There was blood on his bare right foot too that he didn’t see.

He keeps the keys and money and tosses the cell phones into some bushes and leaves the area.

So, perhaps this accounts for the physical evidence that we are aware of, though maybe not, we would need some helpful critique to determine that.

Note that in any event DNA of the boyfriend in the flat is of limited or no use, since it can be presumed he was a frequent visitor there.

Rudy Guede never tells this story because he feels more ashamed of it than the story that he killed Meredith. The boyfriend is never seriously considered by police, who accepted his faulty alibi and focused entirely on Amanda Knox.

Plausible? We think so. We’ll take to the twitters, which is very active on this subject at the moment, and see what the partisans come up with.

Two things, however. First, we are not accusing the boyfriend, simply hypothesizing, trying to fit evidence into an alternative narrative.  And second, we don’t mean to treat this subject like some intellectual game, or a fictional whodunit. We are aware of the tragedy at the bottom of this speculation, we do not wish to fan the flames, but people are discussing the subject no matter what we do or don’t do, and a little rationality can’t hurt, we figure.