r/amandaknox • u/AlanOfTheCult • 26d ago
Negative Control Tests
Today I read something I hadn't seen before in this case. And it's about the Negative Control Tests for the knife.
Apparently Stefanoni straight up refused to provide these when the court requested them.
Can anyone help me confirm if this is true?
Because if this is the case then that is just staggering.
For those unaware: these are blank samples that should be tested alongside the item you want to test - as this helps to identify possible contamination in the equipment.
Considering the level that they were amplifying the samples from the knife one would expect this data to be readily available to the forensics team.
If the Negative Controls were not readily available alone should have been enough to disqualify the DNA result in this case.
At best it would mean they didn't perform the tests: which would be incompetence.
At worst it would mean they did the tests and deliberately suppressed the results: which would be a deliberate misrepresentation of evidence.
If this is indeed the case, I am finding it difficult to come to a conclusion that these weren't mere errors - but deliberate decisions made to misrepresent the evidence that was available to the prosecution.
There's just too many examples.
- "forgetting" that they had negative TMB tests on the footprints.
- Claiming zero contamination despite the bra clasp showing clear signs of contamination, and multiple DNA profiles they deemed irrelevant.
- Lost CCTV footage
- Destroyed Hard Drives
- Missing Negative Control Tests
- Allowing the Bra Clasp to be rendered useless for further examination.
- etc. etc.
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u/SeaCardiologist6207 26d ago
This is true - they were never made available in the Massei case, but when asked by Hellmann to produce them, she first said that it wasn't normal to include them in the technical report. Conti and Vecchiotti specifically called this out as well for BOTH positive and negative controls. You would want positive controls to be able to determine if Stefs actual "experiment" in using the amplification technique beyond its limit actually was working.
I will leave you with this Stef gem from her actual testimony:
"So, the raw data are not available in the case file, because they were never, let us say, handed over."
4
u/AlanOfTheCult 25d ago
Yeah - I saw the quote.
This is actually wild to me that she didn't have these results available to provide to the court or the court-appointed experts.
Having controls in place simply is not optional. ESPECIALLY when you're trying to use equipment outside of its designed specifications.
If she couldn't supply them there's only three options;
- They were lost (incompetence)
- She didn't conduct them (gross negligence)
- She didn't like the results and buried them (criminal).
It's unbelievable that she did this because some jurisdictions wouldn't just toss the one item of evidence - they toss ALL the forensic evidence. This legitimately could have gone so far as to risk Guede's conviction.
How she kept her job after this is beggar's belief.
The fact that the prosecution tried to go so far as to try to blame C+V for the missing control test results is also freaking wild.
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u/Onad55 25d ago
There are two separate issues with regard to positive and negative controls. With every run of the DNA analysis there are slots assigned to positive and negative controls. These controls assure that the reagents are clean and reacting as intended. You can see these controls listed on the quantification records.
But these controls have not gone through any of the other processing that a suspect sample has: collection, swabbing, separation, concentration, etc. They cannot indicate if there is contamination occurring at any of these prior steps.
Stefanoni seems to be total unaware of this issue when she insists that there were negative and positive controls.
There should also be substrate controls to rule out or compensate for environmental contamination in the area where the stain is found. No substrate controls were ever collected.
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u/SeaCardiologist6207 26d ago
I'll add this gem: The prosecution also hired as consultant the chief of the forensics lab that was analyzing the physical evidence for the case. Dr. Renato Biondi was in charge of the lab and it was one of his subordinates, Dr. Patrizia Stefanoni, doing the analysis. This is legal in Italy since it is assumed the analysis will be done objectively.
Like this is basic science. If you collect a murder weapon or actual evidence a control object must be collected from the same place and must be treated in exactly the same way and must test negative for the victim’s DNA. Its a simple standard thats applied to make sure that your "test" worked properly. In this case, not only did Stef not share those controls, or apply controls (no positive control for the knife!) she then doesn't willingly share it, which any confident DNA scientist would do if they were in a murder trial since law has this funny thing called "appeals" and someone might review or question your work.
And then people wonder why we can't find a DNA expert or criminologist who thinks any of Stef's work is worth shit. But hey, MILLANE!
2
u/Etvos2 20d ago
You may want to do a followup post as just recently Colorado Bureau of Investigation analyst Yvonne "Missy" Woods was sentenced to 10 years in prison in part for deleting data from negative control tests.
One particularly telling point is on page 63 of the CBI report when a CBI employee said that,
'[REDACTED] said she wasn't sure why Woods would delete data, because contamination is very common and there are methods to deal with it'.
Now compare this with Patrizia Stefanoni who bellowed that her lab had never ever a single instance of contamination. Never!
I don't believe Stefanoni.
Unfortunately the only copy of the report I can find right now is hosted on Amazon Web Services and it appears to be from the Colorado Sun newspaper but malware scanning the hell out of it might not be a bad idea.
-2
u/FreshFruit4RottenVeg 26d ago
I remember something about this, the defence apparently made a mistake saying the negative controls weren't disclosed but they previously had been. Memory is a bit hazy but I think they were included in the disclosed documents for the Micheli trial with only the actual tests included in the Massei bundle.
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u/AlanOfTheCult 26d ago
Was it the defence? Because in the Conti and Vecchiotti report it says that they were missing. And, when asked about it she said:
"Allora, i dati grezzi non sono disponibili perché non sono mai stati, diciamo, nel fascicolo, consegnati."
"So, the raw data are not available because they were never—let's say—submitted as part of the file."Maybe I'm missing something here?
-1
u/FreshFruit4RottenVeg 26d ago
Found something in the Chieffi report for the Supreme Court ruling that cancelled the Hellman's acquittal:
"The second court endorsed the theory of probable contamination proposed by the experts based on [the theory that] “anything is possible”, which is not a valid argument due to its generic nature, again incurring a logical and legal error: the means of contamination needed to be identified if it was to be used to invalidate the data provided by the [initial] technical report; it was not enough to theorize inadequate professionalism by the operatives during the evidence collection process, especially in a context in which laboratory contamination was mathematically excluded – i.e. the most demonstrable and persistent type of contamination – and in which negative controls were performed by Dr. Stefanoni in order to exclude it, controls which were assumed a little too nonchalantly to be missing by the experts just because they were not attached to the report. The [Court’s] supporting argument, as the appellants held, did not take into account the authoritative dissenting voices on the existence of contamination; no adequate explanation was offered as to why this had affected only some of the traces examined and not others (those most challenging from a defence standpoint); but above all it was based on the erroneous conviction that it was the duty of the prosecution to prove the absence of contamination"
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u/AlanOfTheCult 26d ago
Goodness I always forget how daft the Chieffi Report was. Yes, the experts are going toassume the negative controls are missing, if they're missing in the report.
But, putting that to one side, I'd be interested in seeing when they were actually provided. Because Stefanoni's quotes seem to show reluctance to provide them, if I have understood correctly.
-5
u/FreshFruit4RottenVeg 26d ago
I'm not sure why you think the quote above is 'daft', it is perfectly in keeping with sane, logical reasoning. If what the 'expert' testimony was saying was true, every DNA test performed anywhere could be argued to be due to contamination. 'Anything is possible' is not a reasonable thing for any expert witness to say to the court.
Even when Stefanoni's quote is lifted out of context it doesn't support what you are claiming about a reluctance to provide them. They sent a report of the results to the new 'experts', the report did not contain the negative controls. The experts do not seem to have asked for them but used the fact that they were not initially included to argue they were never performed. They were wrong, their use of assumptions in this case is mind-blowing.
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u/SeaCardiologist6207 26d ago
They specifically requested them, as did Hellmann. The quote is her response to that request, in court.
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u/AlanOfTheCult 26d ago
The 'Anything is possible' line was there because there were about 100 avenues for contamination created by the forensics team.
- Lack of Hairnets
- Object left exposed, and clearly moved around the room, for over 40 days.
- being passed from person to person
- dirty gloves
This is why I'm so critical of the forensics team in this case. Because all of the above is completely unacceptable.
I was an Archaeologist at the time and when an item was encountered where we likely needed to do laboratory testing doing any of the above was considered a cardinal sin. The fact that these were ALL done by a criminal investigation team is embarassing.
The burden of proof being asked of the defence in the Chieffi report is unreasonable. When multiple potential avenues of contamination have been identified you can't then complain that the defence can't tell you which specific avenue caused the specific false positive.
Also Conti and Vecchiotti's report merely stated that the negative and positive controls were not present in the report provided to them.
Which was true.
It was the responsibility of the forensics team to provide them in their report and they didn't.
The prosecution can't whine that Conti and Vecchiotti didn't do their job for them.
I do not see any assumptions in the Conti/Vecchiotti report at all.
Their language is very clear and specific.They followed the accepted processes and were clear in their explanations for why there was possibility for contamination, as well as other flaws in the testing process, in each instance.
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u/jasutherland innocent 26d ago
You have it backwards.
Any test could potentially be contaminated which is why control tests are done to rule it out. Any DNA test performed anywhere without those safeguards can indeed be dismissed as potential contamination - which is the whole point of the safeguards.
Just like the crime scene techs normally have their own prints etc on file, so if they do get found anywhere they are easy to identify and deal with.
We know some of the DNA safeguards were indeed skipped entirely, particularly in the case of the knife: the lab simply wasn't trained or equipped for "LCN DNA" testing. Stefanoni was very complacent about skipping precautions - the court rulings seem to vary a bit on exactly how severe the issue was.
Also remember C&V were not "defence" experts hired to take a side - they were court-appointed reviewers. It was Stefanoni who was working for one side only.
5
u/SeaCardiologist6207 26d ago edited 26d ago
And positive controls are used to test the efficacy of the actual technique used. In most cases that won't matter because in essence, a lab is "following directions". In this case, Stef used a technique that the manufacturer specifically said the machine she was using was not designed for, so positive controls would be critical to both have and to review.
And of course, because she is Rome's top lab, she just thinks that "standard" doesn't even matter.
3
u/AlanOfTheCult 24d ago
Honestly - the way that so many guilters talk about C&V is infurating.
Their report is thorough, comprehensive, and detailed. It covers a range of areas that the original laboratory team should have covered before concluding the knife was the murder weapon.
And guilters will just dismiss them and claim they were making "assumptions" or were paid off.
3
u/jasutherland innocent 24d ago
Yep. I don't know how much is innocent misunderstanding - assuming it's adversarial like the US or UK, where each side brings their own experts in, and how much is just desperation to downplay the court expert findings of the prosecution failings, trying the "both sides" fallacy.
3
u/AlanOfTheCult 24d ago
Indeed - and in this discussion in particular it's frustrating.
Because this isn't the prosecution not giving the defence something they asked for. It's the prosecution not giving the court something they asked for.
And they're just breezing past it as if that isn't a big deal.
0
u/No-Willingness-1441 25d ago
So - am I getting this right…the negative controls were done and provided?
4
u/jasutherland innocent 25d ago
We don't know. They were asked for but, in her own words, "never... handed over".
The lab operated on "trust me bro" instead of following the rules normal labs use.
1
u/AlanOfTheCult 24d ago edited 24d ago
the negative controls were claimed to have been done but the results never provided - despite repeatedly being asked for.
Completely against established norms and standards.I hadn't realised this was the case before, and the reason I was asking for people to help me confirm on way or another.
Because not providing these results would easily the biggest red flag I've seen so far that raises the suspicion that the prosecution were burying evidence.
I can personally accept lost CCTV footage, mishandling of the knife, mishandling of the bra clasp, and a lot of other things in this case as incompetence or errors in the face of massive media coverage and pressure.
But this thing of refusing to hand over key scientific data to court appointed experts is absolutely damning. And the fact that the Chieffi report allowed them to get away with it should be an indictment against the system.
0
u/No-Willingness-1441 25d ago
How is this downvoted?
3
u/SeaCardiologist6207 25d ago
May I ask why you care so much about downvotes?
2
u/No-Willingness-1441 25d ago
Because it’s bl**dy weird to downvote somebody for simply stating a fact. What are we to infer? That you don’t like facts if they don’t suit your narrative? Seems a bit off, no?
2
u/SeaCardiologist6207 25d ago
Define "fact" here. Because what exactly? Some redditor says something happened.
Are you referring to this?
"Found something in the Chieffi report for the Supreme Court ruling that cancelled the Hellman's acquittal:
"The second court endorsed the theory of probable contamination proposed by the experts based on [the theory that] “anything is possible”, which is not a valid argument due to its generic nature, again incurring a logical and legal error: the means of contamination needed to be identified if it was to be used to invalidate the data provided by the [initial] technical report; it was not enough to theorize inadequate professionalism by the operatives during the evidence collection process, especially in a context in which laboratory contamination was mathematically excluded – i.e. the most demonstrable and persistent type of contamination – and in which negative controls were performed by Dr. Stefanoni in order to exclude it, controls which were assumed a little too nonchalantly to be missing by the experts just because they were not attached to the report. The [Court’s] supporting argument, as the appellants held, did not take into account the authoritative dissenting voices on the existence of contamination; no adequate explanation was offered as to why this had affected only some of the traces examined and not others (those most challenging from a defence standpoint); but above all it was based on the erroneous conviction that it was the duty of the prosecution to prove the absence of contamination"
So guilters just get to define "facts"? Its a motivations report. Its the opinion of one judge against another judge who says she did not provide the negative controls.
So we are supposed to assume that if 2 judges disagree, we are to agree with the first one's "narrative"?
Its a simple question that Stefanoni could have answered by simply doing normal stuff like....attaching controls to a report. And not having to be asked by a second court for them.
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u/idledanon 14d ago
It's a fragile, legal kind of freedom. It lacks organic support. Therefore, it must be created.
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u/AlanOfTheCult 24d ago
for the record, I upvoted it. But I think people are likely downvoting the fact that it doesn't answer the actual question and because the Chieffi report had many factual errors.
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u/TGcomments innocent 26d ago
The question of negative controls in terms of 36b is irrelevant since even Nencini threw out 36b for a different reason.
It looks to me that the fact that it couldn't be repeated is the fundamental consideration, so you have 3 courts: H/Z, Nencini and M/B all dismissing 36b due to that reason .