otto,
I would like to compare your work with
Katody Matrass, who analyzed the print at JREF. The reason I asked you to put the mixed DNA in the theory of the crime was so I could decide whether or not it were inculpatory, but you declined.
Very well, all we know about the blob in Filomena's room is that it tested positive for luminol and that it had Meredith's and Amanda's DNA. Luminol is a presumptive test for blood, not a confirmatory test; therefore, you are wrong to talk about Meredith's blood being in Filomena's room. There are problems with the blob as evidence, starting with the fact that the luminol work was done on 18 December, after many non-forensic police had been in the cottage. There is a good chance that biological material of either Amanda or Meredith was transferred into Filomena's room during this period. The boots of one of the forensics workers had a luminol-positive substance on it, as can be seen in one of the photographs. If the material on the boot can be transferred, then we have one of several possible explanations for the luminol reaction.
Another problem with the blobs in Filomena's room is that one of them has extra alleles in it that do not belong to Amanda or Meredith. It was not a complete profile, and Filomena's reference profile was not taken in any case. If the DNA counts as evidence against Amanda, why doesn't it also count as evidence against person X?
I don't think that much should be deduced by the lack of Filomena's DNA, even if the police had been able to identify it. The police should have sampled for DNA a few inches or so away from the blobs. This is called a substrate test (substrate control), and it might indicate whether the DNA deposited had anything to do with the luminol blob. There are luminol-positive blobs in Raffaele's apartment containing Raffaele's and Amanda's DNA. No one asserts that these are part of any crime. Who the idiot is (with respect to my title) is in the eye of the beholder.