The only thing that is established is that the seal on the bag was broken at one point in time. The blood gets into those containers by puncturing the rubber stopper and allowing the vacuum inside to draw in the appropriate amount of blood from either a phlebotomy needle or a syringe. In a adult*, the puncture hole only establishes that blood got into the container.
* when working with small children, I have filled EDTA containers by popping off the top and dripping the blood into them without penetrating the rubber stopper. That was done because we had very limited samples that we needed for several tests and we didn't want all of it get sucked into the first vial. The cell counter, which the EDTA vial is used for, is tolerant to varying concentrations of EDTA in the sample.
I understand how the vacutainer is initially filled. But I believe that the documentary explained that the lawyer called LabCorp, who stated that they removed the cap to analyze the blood and replaced it with a fresh one afterwards.
Also, when I was a paramedic, every vial of blood I ever watched being drawn for forensic purposes was immediately sealed with a barcoded sticker that was attached to the stopper end of the vial itself, extending past the stopper to the glass. Then the sealed vial was placed and sealed into a barcoded bag with the case information written on it, so both the vial and the bag were barcoded and sealed.
I don't know what happened to the samples after that, but apparently the vials are placed in cushioned boxes, which are also barcoded and sealed, and sent to the crime lab. Aren't the vials re-sealed again after the analysis is done? It would seem pretty dumb not to considering that they're forensic evidence.
Whatever the case, however, in the Avery case, the evidence box itself was obviously and illegally unsealed, there was no record of any court order authorizing it, there was no record of it even having been done, and the only people with access to it were either LEOs or people from the prosecutor's office. That doesn't definitively prove that someone accessed the blood for evidence-planting reasons; but really, what other reasonable explanation is there for someone illegally unsealing and accessing a blood sample?
I'm not the sort of person who believes that cops in general are corrupt or would plant evidence. In fact, I think that's extremely rare. But it's hard for me to come up with a reasonable explanation for this particular sample, in this particular case, having been accessed and unsealed. There is no reasonable alternative motive, and no one else had physical access to it.
Can you come up with any non-malicious reason for that sample having been clandestinely accessed and unsealed, without authorization or documentation, that isn't outlandish? The only reason I can think of is an outlandish one: that some nut job wanted a sample of Avery's blood to auction off on eBay or for some similarly morbid collector reason.
Finally, the very fact that the evidence was
able to be accessed and tampered with without authorization nor documentation doesn't speak well of the evidence-safeguarding and chain-of-custody procedures that were in place.
So in the end, I still have to say that I would have voted to acquit, not because I would have been sure that Avery was innocent, but because my confidence level in the integrity of Lt. Lenk, the evidence-safeguarding procedures in place, the chain of custody, and therefore the integrity of the evidence itself, would have been sufficiently damaged as to create reasonable doubt in my mind.
Rich