There was no great knowledge as to whether there was drawback or not. As far as I am concerned it was a gamble that paid off for those who wanted JB convicted. I repeat what I have believed from the very beginning. The silencer was faked evidence by those to whom it would benefit the most. They needed no great knowledge whatsoever. As a well known magician once said, "Scientists are the easiest people to fool".
The evidence that it was drawback was un-rebutted and thus effectively conceded by the defense- particularly with the defense contending June and Nevill's blood got inside while being shot.
Establishing who the blood belonged to was established by the prosecution int he following manner:
1) Sheila suffered a contact wound that would result in drawback. That means Sheila's blood would have to have been deposited in the muzzle of the rifle or the moderator if the moderator were attached to the rifle when the shot was fired
2) No blood was found int he rifle but blood consistent with Sheila's was found in the moderator
3) It is unlikely June and Nevill suffered any wounds that were contact wounds that could have resulted in drawback and the twins did not suffer any contact wounds that would result in drawback
4) visible blood was found on the first 5-7 baffles which was determined to be from one person and it was group A blood
5) a flake of blood from 1 person that was between baffles 1 and 2 was group A blood and also had enzyme AK1.
6) June and Sheila both have group A blood but Sheila has enzyme AK1 while June has enzyme AK2-1 so the flake was consistent with Sheila's blood not June's
7) AK2-1 is more hardy than AK1 and since the AK1 enzyme had not yet deteriorated that means had June's blood been present her AK2-1 enzymes would still have been present. So this speaks against the blood on the baffles or the flake containing any of June's blood because there was no AK2-1 present and there should have been if her blood was present because AK2-1 takes longer to deteriorate than AK1 and AK1 was present.
All of these things combined- the lack of a wound that would result in June's blood getting inside, the fact Sheila did have a wound that would result in drawback and that none was found in the rifle, the lack of AK2-1, etc all combined lead to the conclusion the group A blood found inside the moderator was Sheila's.
A competent advocate first makes the effort to FULLY understand the argument of the other side. Then makes an attempt to see if it is possible to rebut the arguments of the other side with competent evidence that can be marshalled.
You just gloss over the argument made at trial and say you don't want to believe it and you feel it means nothing. That's not rebutting the evidence it is simply ignoring it. That accomplishes nothing in a debate. It especially accomplishes nothing when someone was convicted upon the basis of the evidence and the only way to get the conviction vacated is to refute the evidence used at trial.
