Tuesday, June 21, 2011

III. The Verdict in Perugia: the Case Against Amanda Knox and Raffaele Sollecito (Part Three)

This is the third part in a series. Please read the earlier parts to understand the entire article!

IV The Court's Reasoning Explained (continued)

As stated earlier, the basic reasoning behind the verdict is the following.

A. Guede is guilty of the murder;
B. Guede did not act alone;
C. the only possible accomplices of Guede are Knox and Sollecito;
D. that Knox and Sollecito are culpable of the murder is corroborated by the forensic evidence available;
E. and it is also corroborated by the fact that their stories don’t seem to be logical and do not constitute convincing alibis.

The first two points (Guede's guilty, and the notion that he did not act alone) have been adressed in Part II of the series. Points C and D (Guede's accomplices and the corroborating evidence of their guilt) are discussed here. Part IV of the series will look at Knox's and Sollecito's alibis. The fifth and final part of the series will discuss the appeal proceedings and contain some closing thoughts.

C. The accomplices were Amanda and Raffaele

The court considers that only Knox (and Sollecito) could have any real motive for staging the break-in. The reason for this is almost self-explanatory. Staging the break-in must have been an attempt to divert attention towards one or more hypothetical “outsiders”. It must, therefore, have been done by one or more “insiders”. The only insider that can possibly be taken into consideration is Knox. I point out that, in theory, one might also consider the two Italian girls living in the apartment on the first floor, or, indeed, the four boys living downstairs. All of these seem to have had, however, watertight alibis (they simply weren’t there), and no evidence whatsoever was found to even remotely implicate any of them.

Simply by a process of elimination, therefore, the only “insider” remaining is Knox.

D. The corroborating evidence regarding Amanda and Raffaele

The following biological evidence was discovered linking Knox and Sollecito to the crime:

– Sollecito's DNA was found on Kercher’s bra clasp;
– Kercher’s DNA was found on the blade of a kitchen knife found in Sollecito’s kitchen;
– blood and mixed DNA traces were found in the small bathroom;
– further mixed DNA traces were discovered elsewhere in the apartment.

The Bra Clasp

As stated, Kercher’s bra had been cut loose. One of the bra clasps (the metal and a small bit of cloth) had been cut from the rest of the bra. The clasp was not initially secured as evidence when the forensic team examined the apartment on November 2nd and 3rd; in fact, it was only secured on December 18th, during a further search of the apartment. It was then taken and examined for DNA, and a trace of Sollecito’s DNA was found.

When it comes to the clasp, there is, I believe, little discussion with regard to the DNA testing itself. The problem that does exist, however, is related to the question of how that DNA actually got on the clasp. Because of the very late securement of the clasp, there is a threat of contamination. Such contamination may have happened sometime during the weeks between the murder and the securement; it could also, perhaps, have happened on December 18th (when the clasp was secured).

In addressing these issues, the court relies heavily on the testimony of the police and the forensic experts involved. Its reasoning boils down to the assumption that no contamination could have taken place before December 18th, because the clasp was in Kercher’s room all this time and was not handled by anyone. No contamination took place on December 18th, because the forensic experts took the precaution of donning clean gloves before handling the clasp. One fact remains, however: sometime during November 2nd (or 3rd) and December 18th, the clasp was moved; it was found in December one and a half meters or so from the place where it was filmed on November.

The Kitchen Knife

With regard to the kitchen knife, other problems arise. The DNA found on the blade was minute; in fact, it was used up during the DNA testing. There was and is no way of repeating the test. Furthermore, the amount of DNA was so small that a method of testing had to be used (known as “low copy number”, or LCN testing) that could be considered less reliable. In other words, the results of the test itself are a matter of debate. In particular, the defence argued that it was unclear whether it was actually Kercher’s DNA that was found, and that even if it were, this could readily be explained by some form of contamination within the laboratory that conducted the testing.

Again, the court rejected the defence claims. Again, it relied heavily on the testimony of the DNA experts, in particular the statements made by dr. Patrizia Stefanoni, who worked with the Scientific Police (the Polizia Scientifica) in Rome and lead the DNA investigations. Dr Stefanoni explained how the tests were conducted, pointing out that no contamination could have resulted from the method used.

It should be noted that there are further issues concerning the knife. These have to do with the wounds inflicted on Kercher’s body. The court finds that some of these wounds (in particular, the wounds on the right side of the neck) could not have been made by the kitchen knife; it was just too big. With regard to the wounds on the right side, the court finds that the wounds are compatible with a knife of this side, but one has to assume that the knife was not used with great force. The kitchen knife had a blade some 17.5 cm long; the most grievous wound was, however, just 8 cm deep. The court explains this by looking at what it assumes was the rationale behind the attack on Kercher: the perpetrators did not, according to the court, at first wish to kill her; they wished instead to force her into complying with their sexual intentions.

Moreover, there is the simple question of how the knife came to be used in the attack against Kercher in the first place. If this was a kitchen knife belonging to Sollecito, how did it end up at the Via della Pergola? The court considers this question, but only briefly: it decides that Sollecito may very well have given the knife to Knox as protection, in which case she was carrying it around in her handbag.

The Blood and Mixed DNA Traces in the Small Bathroom

In various places in the small bathroom (the bathroom used by Knox and Kercher) blood traces were found, and it was determined that the blood belonged to Kercher. This was true, for example, with regard to a trace found on the lightswitch and a trace found on the door; it was true also of a bloody footprint (made by a naked foot) found on a mat in the bathroom. This means that (at least) one person entered the bathroom covered in Kercher’s blood, and at least one person entered who was barefoot.

The first thing to remark is that this again rules out the single-perpetrator scenario. It should be recalled that there is another set of footprints (shoeprints) which led directly from Kercher’s room to the front door; it is impossible to imagine that just one person managed to leave both those shoeprints and the traces found in the bathroom.

The second thing to consider is that whoever entered the bathroom obviously did so after having killed (or assisted in killing) Kercher and did so in order to clean himself (or herself).

Besides these blood traces, there were mixed DNA traces found in the bathroom (in particular: on a box of Q-Tips, and in the bidet and the sink). “Mixed” in this case means that the traces provided, upon testing, both the DNA of Knox and Kercher. It should be noted that whilst the traces did contain blood, that blood came from Kercher, and not (necessarily) from Knox as well. However, the traces did also contain the DNA of Knox, and this, the court decides, is most readily explained when one assumes that Knox had entered the bathroom to clean Kercher’s blood from her body.

As to the footprint, a different conclusion is reached: the evidence with regard to the size and shape of the foot that led to the print leads the court to assume that it was made by Sollecito.

It is pointed out that the defence did not contest the mixed samples; they simply stated that the existence of Knox’s DNA was to be expected when the samples are taken from a bathroom used by her. As to the footprint, the defence argued that, depending on how the print was analysed, one might also conclude that it had been made by Guede.

Further Mixed DNA Traces

Various further traces were found elsewhere in the apartment. This was done after the use of Luminol, a substance that can reveal the presence of blood traces invisible to the naked eye. Two of these are of particular interest: a trace taken in Romanelli’s room, and a trace taken in the hallway in front of Knox’s room. Both traces again contained the mixed DNA of Knox and Kercher.

One should realise that the use of Luminol and the DNA samples subsequently found should be taken in context. Luminol causes a chemical reaction when applied to blood, but it reacts equally to various other substances, such as fruit juice. DNA will provide the genetic profile of individuals, but it is often difficult to establish from what source (blood, exfoliated cells, sweat etc.) that genetic material has come from. When taken together, however, the two can clearly be important.

When it comes to the two samples found in Romanelli’s room and the hallway, the court acknowledges the relevance of the combination. In particular, the court finds that in both cases, a reasonable supposition is that the traces consisted of the blood of Kercher, mixed with the DNA of Knox. Again, the court concludes that this attests to Knox’s presence in the apartment on the night of the murder, and that Kercher’s blood was on her body.

Once more, the defence did not specifically contest the DNA testing or the mixed DNA; it again only pointed out that the presence of Knox’s DNA was to be expected in the apartment where she lived. However, it should be noted that the DNA found was again very small and required LCN testing; in that sense, the objections raised by the defense with regard to Kercher's DNA on the knife apply equally here.

(The court's verdict will be discussed further in Part IV of this series.)

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