The silencer which as checked for DNA as part of the failed 2002 appeal should be checked for the presence or otherwise of superglue residue (cynoacrylate fumes), since I do not think that the silencer which was subject of the an examination in 2002 was coated in white powder from the superglue treatment, spoken about by DI Cook (soc)?
I also do not think that the silencer which was checked for dna in 2002, had a distinctive scratch m,ark running along its length - this would be easy to check and establish, and could help to demonstrate that there were two different Parker hale silencers which found their way into the possession of Essex police...