Im not sayin in shouldnt be, it was and im all for it
just not v surprising it was inconclusive
yes dna can last.. thousands of year in ideal condition, enclosed, protected from light, and cold - as part of a solid body of matter
but in the case of knife with only touch dna and surface stainin at most?...
I've seen cases recently where it's been claimed full DNA profiles have been obtained from just a few cells of so-called touch DNA many years later, without any sort of preservation (which is, in part, how they justify cold case reviews).
I don't know that touch DNA would have been advanced enough in 2010 but, if the knife had a wooden handle, it's likely there would be trace DNA soaked into the wood or trapped in rivets and the groove where the metal of the knife slots into the wood.
David1819 said
If the DNA results were “inconclusive” that indicates to me they found partial DNA profiles that Luke or Jodi could not be excluded from
Don't you think they would have said that, if it's what they meant? The article doesn't even say the police said results were inconclusive - it says, and I quote, "DNA tests on the knife are said to have proved inconclusive." - Said by whom?
As I said before, you can't know what's inconclusive if you don't know what they were looking for. If it was DNA from Jodi or Luke, they didn't find anything that would allow them to conclude that the knife came into contact with either of them, therefore, no claims about the knife as the murder weapon (or as ever having belonged to Luke Mitchell) can be made. However, that result (inconclusive) could still stand, even of DNA from someone else was found, if the parameters of the test instructions were "to find any DNA matching Luke Mitchell or Jodi Jones."