I’ve given you three sources for that in footnote 3 in “The Bury ID.” David, if you intend to be a serious participant in the conversation about the signature evidence linking Bury to the Ripper murders, please consider making some effort to familiarize yourself with the signature analysis literature. A good book for you to obtain would be Serial Violence: Analysis of Modus Operandi and Signature Characteristics of Killers by Keppel and Birnes.
Although you have quoted me saying:
"Firstly, where is your authority that variation is an established characteristic of signature evidence? It will make a nonsense of the word "signature" if that's true."
You appear to have completely missed it when I said:
"Secondly, and far more importantly, do you have even one example of a legal case where signature evidence has been admitted in evidence in a murder case (or even another serious crime) where there are significant variations between the signatures in different crimes?"
You didn't respond to that so I assume you don't have any examples.
As for your response to the first point I don't think I need to look at the book you refer to because in the 2005 Keppel et al article to I read this on page 14:
"Experience and confidence will shape and modify an offender’s MO. Signature characteristics, or a killer’s calling card, are those actions that are unique to the offender and go beyond what is necessary to kill the victim. While MO can change over time and reflect the nature of the crime, signature characteristics remain stable and reflect the nature of offender. Although an offender’s signature may evolve, the core features of the signature will remain constant (Douglas & Munn, 1992a; 1992b; Douglas & Olshaker, 1997; Geberth, 1996; 2003; Keppel & Birnes, 1997; Keppel, 1995a; 1995b; Keppel, 2000; 2004)."
So that seems pretty clear to me. The "core features of the signature will remain constant". If the "core features" of the Ripper's signature were the 11 features listed by the authors of the article, one would have surely expected them to remain constant from murder to murder. But they are not constant in this case.
“First, can we, as an investigative body, satisfy ourselves that William Bury was Jack the Ripper? The answer to that is “yes.”
I’ve just read through the thread but found it rather difficult to get past this statement. The answer should have been a categorical ‘no.’
You appear to be arguing for the importance of signatures on the one hand whilst accepting that they can vary greatly from murder to murder or that some signatures can even be absent due to circumstances (but as long as we understand those circumstances we can excuse their absence.) Surely this is rather shaky ground to be driving such confident stakes into?
Bury is, in my opinion, a reasonable suspect. But there is no suspect yet that we can positively link to all of these crimes. Though I’m no expert in the legal system I fail to see how a prosecution could even get a case together that would have the remotest chance of convincing a jury of Bury’s guilt. Far more real evidence would be required. Behavioural evidence surely cannot be considered to carry the same weight as physical evidence? Behaviour is too much a variable; subject to outside influences. And at a distance of 130 years we are in no position to judge those variables.
"There is nothing more deceptive than an obvious fact!"
Virtue signalling or not, is it possible that Ellen Bury hanged herself? Of course it is. Doesn't mean she did, but it's still possible in light of the evidence, whether Bury had been (mis)sentenced to death or life imprisonment.