We also know that David Boutflour used a razor blade to 'scrape' a small dried flake of blood from the same flat surface of the same silencer, and that Essex police were aware of what he had done, and what's more, we know that this flake of blood was the size of a match head, and that David Boutflour had removed it from the end of the silencer because he said, it 'fascinated' him...
So, he handles the silencer and afterwards human / animal blood is found to be present on the outside of it, in the exact location where he would have needed to place one of his hands whilst attempting to 'unscrew' it. He then, supposedly uses a razor blade to remove a small flake of blood from the end cap of the same silencer, which he says he 'retained' because it fascinated him. He adds that Essex cops knew about all of this, and we have 'Ron' Cook taking this silencer to the lab' to be examined by Glynis Howard on the 13th August 1985, minus the small flake that Boutflour has removed from it. At the Lab', on that date (13th August 1985) we have Howards lab' assistant, 'A BAKER' confirming that the blood from stain (1) originated from an intimate mixture human / animal (rabbit) bloods...
(A) - Human / animals (rabbit) blood at stain (1) by 13th August 1985...
(B) - Human / animals (rabbit) blood in flake (AK/1) examined at lab' between 12th to 19th September, 1985...
The flake which David Boutflour had scraped from the extreme end of the silencer, could only have originated from the same area as stain (1) as depicted in the diagram, dated, 13th August 1985, so therefore, it would be fair to assume that 'the flake' Boutflour took from the outside of the silencer must have also contained the same human / animal (AK/1) bloods, found in stain (1) by 'A. BAKER', on the 13th August, 1985, and which were also present in the flake...
This raises a serious question which requires rigorous investigation into trying to establish whether or not (a) the flake David Boutflour took from the silencer, and (b) the flake results relied upon during the trial, were, one and the same?