Independent Experts Set the Record Straight
July 25, 2011, was a very important day for Amanda and Raffaele as forensic experts Stefano Conti and Carla Vecchiotti, from Rome’s Sapienza University arrived in court armed with laptops, a projector, and piles of paperwork, detailing their analysis of the DNA evidence that would ultimately decide the fate of Amanda and Raffaele. It is important to keep in mind that Conti and Vecchiotti were appointed by the court. Many news outlets reported that they were defense experts, which was not the case.
Conti and Vecchiotti were given the job of providing an unbiased analysis of the DNA evidence presented at the first trial. When Judge Hellmann appointed Conti and Vecchiotti, he was essentially giving them the power to decide the future of Amanda and Raffaele. Injustice in Perugia has repeatedly stated throughout the course of the trial that the truth would eventually prevail. This philosophy has had its critics due to the events that have been witnessed throughout this case but Conti and Vecchiotti’s testimony would go a long way to show that the power of truth was still alive and well.
In a major victory for the defense, Conti and Vecchiotti concluded that the alleged murder weapon and the DNA laden bra clasp used to convict Amanda and Raffaele were unreliable and cited multiple errors made by investigators. Conti and Vecchiotti’s testimony was especially critical of the prosecution’s forensic expert Patrizia Stefanoni who not only supervised the evidence collection at the cottage but also conducted the analysis at the lab.
Conti and Vecchiotti’s testimony was described as “shocking” as sound bites of their scathing criticism blazed through news outlets worldwide, and though it may have been shocking to casual followers, for many it came nearly four years too late.
A recap of the knife: The knife was the prosecution’s “smoking gun” said to have Amanda’s DNA on the handle and Meredith’s DNA on the blade. An investigator claimed he retrieved the knife from Raffaele’s kitchen drawer because it looked clean. Investigators neglected to test any other knives from either Raffaele’s kitchen or the kitchen at the location of the murder, quickly concluding they had found the murder weapon. The knife was suspect from the start not only because of how it was found but also because it was too large to cause Meredith’s fatal wounds and did not match a bloody imprint of a knife found on Meredith’s bed sheet.
Conti and Vecchiotti’s conclusion: There was no blood on the knife, no DNA from the victim, no evidence whatsoever to show that the knife was involved in any way. They did confirm Amanda’s DNA on the handle which was expected because she used the knife for cooking at Raffaele’s apartment. Conti and Vecchiotti also discovered starch from rye bread on the knife blade which was consistent with fact that is was used for cooking. Conti and Vecchiotti’s analysis was far more powerful than any defense expert could present because it came from an independent voice, appointed by the court. The truth was finally crystal clear; the knife in question was not the murder weapon.
A recap of the bra clasp: The clasp was horribly mishandled by investigators and should have never been admissible as evidence in the first place. The defense experts did an excellent job of discrediting the clasp during the first trial but their analysis was ignored. Just like the knife evidence, the damming analysis would be heard from independent voices on appeal, and these voices would not be ignored.
The prosecution claimed the clasp, which was torn from Kercher’s bra during the attack, contained Raffaele’s DNA. No other evidence linked either Raffaele or Amanda to the murder room making the clasp vital to the prosecution’s case. Several factors discredit this piece of evidence. Investigators neglected to collect the clasp for 47 days leaving it to be shuffled around on the floor as seen in crime scene video throughout that time frame. When the clasp was finally collected, multiple investigators handled it with contaminated gloves. Conti and Vecchiotti detailed the clear negligence witnessed during the evidence collection but more importantly, they reported that Patrizia Stefanoni erroneously interpreted the electrophoretic profile when she concluded that Raffaele’s DNA was present on the clasp.
The method Stefanoni used centers in on a specific suspect, a practice that is forbidden by all international standards due to the fact that it leads to biased analysis. Samples are to be analyzed individually and then the final results are compared to see if any produce a positive match. If one begins knowing what they are looking for already, they are likely to interpret the electorpherogram to match the result they are trying to achieve. Conti and Vecchiotti explain as follows:
“Statements about a profile obtained from a sample under examination, regarding the decision as to which is a true allele and which a 'drop-in', must necessarily be pronounced without knowledge of the suspect's profile; only in such a way, in fact, can a qualitatively unimpeachable and balanced approach to the interpretation of the profile emerging from the sample in question be guaranteed. An interpretation of the profile obtained from a sample, carried out with the suspect's reference profile available, indicates an imbalanced [approach], and is in total contrast with the absolutely objective nature of forensic science”
Stefanoni not only violated protocol, but also lied about it in court when she stated that she had adhered to proper procedure and analyzed all traces in an absolutely objective manner. Her boss, Dr. Renato Biondo, head of the DNA Unit at Polizia Scientifica, Rome, and consultant for the prosecution, needed positive results from Stefanoni and she was more than willing to fulfill the request.
Stefanoni lied in court again, claiming that stains detected at the crime scene using luminol (an investigative tool used to detect blood not visible to the human eye) were never tested for blood; however, in July 2009, when pressured by the defense, Stefanoni released information originally withheld confirming the stains were tested with tetramethylbenzidine, which is extremely sensitive for blood. All of the stains detected with luminol tested negative for blood. Stefanoni held this information from the court testifying instead that the stains were indeed blood. This is yet another example where Stefanoni created evidence to benefit the prosecution.
But Stefanoni’s lies do not end there. She also lied when she testified that she changed gloves every time she handled a new sample. However, Raffaele Sollecito’s defense used clear video and photographic evidence to show that Stefanoni used the same gloves multiple times while collecting samples. This lie was highlighted once again by Conti and Vecchiotti during the appeal.
It is clear that much of the blame belongs to Patrizia Stefanoni, who lied repeatedly in court to benefit the prosecution. The independent experts cited egregious violations committed by Stefanoni that clearly shows she had an agenda.
It is shocking that police negligence did not play a much larger role in the first trial. Much of the evidence collection was captured on video and many cases of faulty procedure and quite frankly odd behavior can be viewed throughout the entire collection process.
Conti and Vecchiotti used video taken during evidence collection in court to show negligence. Testimony from Stefanoni defending her work was read to the court followed by video clips showing that she was being less than honest in her own defense. The examples of negligence were so ridiculous that the court burst out in laughter on several occasions during the presentation. It is hard to imagine that anyone could actually laugh out loud during a serious trial such as this, but sometimes things are so absurd that laughter is the only possible emotion.
The truth is investigators completely mishandled the crime scene causing much of the evidence to be susceptible to contamination. More importantly, the court accepted the evidence, leading to the wrongful conviction of Amanda Knox and Raffaele Sollecito.
Here is an English translation of the conclusions reached by the independent court appointed experts Stefano Conti and Carla Vecchiotti.
Based on the considerations explained above, we are able to respond as follows to the inquiries posed at the assignment hearing:
"Having examined the record and conducted such technical investigations as shall be necessary, the Expert Panel shall ascertain:
1. Whether it is possible, by means of a new technical analysis, to identify the DNA present on items 165b (bra clasp) and 36 (knife), and to determine the reliability of any such identification"
- The tests that we conducted to determine the presence of blood on item 36 (knife) and item 165B (bra clasps) yielded a negative result.
- The cytomorphological tests on the items did not reveal the presence of cellular material. Some samples of item 36 (knife), in particular sample "H", present granules with a circular/hexagonal characteristic morphology with a cental radial structure. A more detailed microscopic study, together with the consultation of data in the literature, allowed us to ascertain that the structures in question are attributable to granules of starch, thus matter of a vegetable nature.
- The quantification of the extracts obtained from the samples obtained from item 36 (knife) and item 165B (bra clasps), conducted via Real Time PCR, did not reveal the presence of DNA.
- In view of the absence of DNA in the extracts that we obtained, with the agreement of the consultants for the parties, we did not proceed to the subsequent amplification step.
2. "if it is not possible to carry out a new technical analysis, shall evaluate, on the basis of the record, the degree of reliability of the genetic analysis performed by the Scientific Police on the aforementioned items, including with respect to possible contamination."
Having examined the record and the relevant documents, we are able to report the following conclusions regarding the laboratory analyses performed on Item 36 (knife) and Item 165B (bra clasps):
ITEM 36 (KNIFE)
Relative to the genetic analysis performed on trace A (handle of the knife), we agree with the conclusion reached by the Technical Consultant regarding the attribution of the genetic profile obtained from these samples to Amanda Marie Knox.
Relative to trace B (blade of the knife) we find that the technical analyses performed are not reliable for the following reasons:
1. There does not exist evidence which scientifically confirms that trace B (blade of knife) is the product of blood.
2. The electrophoretic profiles exhibited reveal that the sample indicated by the letter B (blade of knife) was a Low Copy Number (LCN) sample, and, as such, all of the precautions indicated by the international scientific community should have been applied.
3. Taking into account that none of the recommendations of the international scientific community relative to the treatment of Low Copy Number (LCN) samples were followed, we do not accept the conclusions regarding the certain attribution of the profile found on trace B (blade of knife) to the victim Meredith Susanna Cara Kercher, since the genetic profile, as obtained, appears unreliable insofar as it is not supported by scientifically validated analysis;
4. International protocols of inspection, collection, and sampling were not followed;
5. It cannot be ruled out that the result obtained from sample B (blade of knife) derives from contamination in some phase of the collection and/or handling and/or analyses performed.
ITEM 165B (BRA CLASPS)
Relative to Item 165B (bra clasps), we find that the technical analysis is not reliable for the following reasons:
1. There does not exist evidence which scientifically confirms the presence of supposed flaking cells on the item;
2. There was an erroneous interpretation of the electrophoretic profile of the autosomic STRs;
3. There was an erroneous interpretation of the electrophoretic profile relative to the Y chromosome;
4. The international protocols for inspection, collection, and sampling of the item were not followed;
5. It cannot be ruled out that the results obtained derive from environmental contamination and/or contamination in some phase of the collection and/or handling of the item.
The conclusions reached by Conti and Vecchiotti constitute a damning indictment of the investigation conducted by Italy’s Scientific Police, and in particular of the methods employed by the prosecution’s main forensic scientist, Patrizia Stefanoni. They lend official support to the already-widespread perception that Amanda and Raffaele have been the victims of a scandalous miscarriage of justice.