Best evidence for left/right/mixed-handedness

[Elamarna]

Please give some indication of to whom you are addressing above please.

Jon,
my point was really about people being clear about the thread.
The first 12 posts were all about comments by Dr Biggs, after which there was a gap and then people again posted and reading those posts it was easy to gain the impression that people were not reading all the posts, as there appeared to be an no reference to those early posts, which if disagreeing with i would expect to be mentioned, even if only in passing.

if that had happened after say another 5 or 6 pages i could understand it more, as a thread gets longer it is obviously hard to read all of it.

Kattrup has made it clear that he had, I certainly assume you had.

Once again it is was aimed at clarity from posters rather than any individual, which I think will be clear from my responses to Kattrup and hopefull from this post as well.

regards

Steve

[Jon Guy]

And most importantly whether the victims were standing up or lying down when their throats were cut.

www.trevormarriott.co.uk

Nichols, Eddowes and McKenzie were on their backs when their throats were cut.

[Jon Guy]

The basis on which it is possible to determine on, say, balance of probabilities, whether a perpetrator is left or right-handed. In other words, an objectively reasoned argument supported by authority.

Hi John

For which victim ?

[Jon Guy]

Now of course everyone is free to comment on this thread, such debate is always healthy, but from some of the recent posts it seems not all are bothering to read the first 12 posts on the thread, a point already raised by John G.
By all means disagree with Dr Biggs, after all it is only the opinion of one man, an expert in forensic pathology; but please at least give some indication that you have read the comments he made; otherwise this may as well be a different thread.

Please give some indication of to whom you are addressing above please.

[Kattrup]

Lets put that behind us, is that ok?

Absolutely

The basis on which it is possible to determine on, say, balance of probabilities, whether a perpetrator is left or right-handed. In other words, an objectively reasoned argument supported by authority.

Thanks for clarifying; no, I cannot provide such references. I don't know if any exist, but I consider it unlikely.

I posted in this thread about what I think is the best evidence regarding the killer being left- or righthanded.

It doesn't mean that I think it's possible to determine beyond doubt. But it does mean that I believe one can theorise about it in an objective and reasoned manner supported by the sources.

[Pierre]

[QUOTE=Trevor Marriott;373562]

I asked Dr Biggs detailed questions about this issue here is his reply

Hi Trevor and everyone,

There are some problems with the reply of Dr Biggs. Firstly, he says:

"It is really impossible to say with certainty how the wounds were inflicted in terms of ‘reconstructing’ events from the appearance of wounds.

"With certainty" does imply a binary option with certainty/with no certainty. But if research has been done on the subject, what we would want is research based on statistics and hypothesis tests. We would like scales, not a binary variable. Biggs does not refer to such tests. So the answer is not relevant for our question.

Secondly, "reconstructing events" is a very wide concept, not operationalised as "examining probability for left-handedness" (which we are asking for). So it is not a valid statement.

This is something that used to be quite ‘popular’ even up until relatively late on in the 20th century, with pathologists stating confidently that a left-handed dwarf with a limp inflicted the injury from behind using a specific knife, etc.

I think that a person who is speaking about a "dwarf with a limp" when asked an important researched question should not be taken seriously and is not a reliable reference.

Nowadays it is accepted that there is so much variation that in such cases, apart from a few ‘extreme’ scenarios that can be more-or-less excluded, just about anything is possible.

That statement is a sweeping generalization - and we could make generalizations if we give an account for the base for it. But there is no such account. Therefore, we do not know what this sweeping generalisation is based on. And with "sweeping" I mean that it is not well defined.

So in other words, the killer could have been behind the victim (with them both standing), or he (or she!) could have been ‘above’ the victim (kneeling, squatting, crouched, lying, stooping…) whilst she lay upon the ground (+/- prior strangling). Or it could have happened during a highly dynamic struggle, with all manners of grappling, twisting and fortuitous slashing going on. Only persons present at the time really know what went on (and we can’t ask them!), and nobody can be certain about a ‘reconstruction’ now based on photos / medical records"

The question which he is trying to answer here, if he does that, is another question than the one I posed. The question here is "Where was the murderer?

If a number of envisaged scenarios are actually ‘possible’, then nobody can really argue in favour of a particular one any more than another.

Here, we are simply "told" what we can not do. On what grounds is not accounted for.

www.trevormarriott.co.uk

Conclusion: I think the ideas of Biggs are useless for our question.

Regards, Pierre

[Elamarna]

[QUOTE=Kattrup;376399]I certainly did not mean to be overly confrontational, except to the extent that I disagreed with your post, which is of course a confrontation of sorts.

I therefore apologise, but I felt that your post, the third of its kind in this thread, was partly directed at me, since I'd posted after the commenting lull you mentioned.


Hi kattrup,

Lets put that behind us, is that ok?

am sure you are aware there is little helpful crime scene evidence, and the only useful recording of blood splatter is in the Kelly case.
However have you read the Article Cut Throat by Karyo Magellan, very interesting read when looking at this particular area. dispels many of the myths around the neck wounds.
the link to it is:

http://www.karyom.com/

cheers

Steve

[John G]

I certainly did not mean to be overly confrontational, except to the extent that I disagreed with your post, which is of course a confrontation of sorts.

I therefore apologise, but I felt that your post, the third of its kind in this thread, was partly directed at me, since I'd posted after the commenting lull you mentioned.



I'm not sure what you're asking me to support, I don't think I'm making any wild claims in my post?

The basis on which it is possible to determine on, say, balance of probabilities, whether a perpetrator is left or right-handed. In other words, an objectively reasoned argument supported by authority.

[Kattrup]

Dear Kattrup

There is of course plenty of evidence which one could work from, my point was that some, appeared from their comments, not to have read Biggs comments.

I certainly did not mean to be overly confrontational, except to the extent that I disagreed with your post, which is of course a confrontation of sorts.

I therefore apologise, but I felt that your post, the third of its kind in this thread, was partly directed at me, since I'd posted after the commenting lull you mentioned.

Can you please cite authority to support these arguments. Or is this more of a hunch?

I'm not sure what you're asking me to support, I don't think I'm making any wild claims in my post?

[John G]

Well, I've of course read the thread and Trevor Marriot's overly curt insistence that further debate is pointless.

You seem to accept his stance.

A fair question might be has he, or have you, read Dr. Biggs' statement?

The expert pathologist states that it is not considered possible from the appearance of the wounds to determine whether it was caused by a left- or righthanded man.

This is, I believe, uncontroversial in today's forensics. It only means, however, that once the body is taken away, wounds washed, studying the wound itself will not reveal from which direction it was inflicted.

It does not mean that no other evidence should be taken into consideration, nor that it is impossible to infer whether the culprit was most likely right- or lefthanded.
A right-handed man attacking another from the front will inflict the majority of the wounds on the left side of the victim. Of course, a left-handed man attacking from the left side of the victim will too. So there are other types of evidence than merely analysing the appearance of the wounds (also blood splatter patterns could be analysed).

As stated, I believe that the sources describing the victims, the locations of their wounds and the crime scenes give indications as to the killer's handedness. This does not conflict with the learned Dr. Biggs' statement.

Furthermore, this thread is about which evidence is best - thus, even if we don't accept the judgement of the medical examiners of the time, their statements are still our evidence, and can therefore be considered (even if ultimately discarded).

Furtherfurthermore, even though I do not believe one can trust their judgement (because we now know that it is not possible to be certain), the fact that they believed that they could, in fact, determine probable handedness, is in itself of some interest, for instance to historians of forensics. That might belong in another thread, of course, but it's possible that Pierre has this aspect in mind.

Can you please cite authority to support these arguments. Or is this more of a hunch?

[Elamarna]

Well, I've of course read the thread and Trevor Marriot's overly curt insistence that further debate is pointless.

You seem to accept his stance.

A fair question might be has he, or have you, read Dr. Biggs' statement?

The expert pathologist states that it is not considered possible from the appearance of the wounds to determine whether it was caused by a left- or righthanded man.

This is, I believe, uncontroversial in today's forensics. It only means, however, that once the body is taken away, wounds washed, studying the wound itself will not reveal from which direction it was inflicted.

It does not mean that no other evidence should be taken into consideration, nor that it is impossible to infer whether the culprit was most likely right- or lefthanded.
A right-handed man attacking another from the front will inflict the majority of the wounds on the left side of the victim. Of course, a left-handed man attacking from the left side of the victim will too. So there are other types of evidence than merely analysing the appearance of the wounds (also blood splatter patterns could be analysed).

As stated, I believe that the sources describing the victims, the locations of their wounds and the crime scenes give indications as to the killer's handedness. This does not conflict with the learned Dr. Biggs' statement.

Furthermore, this thread is about which evidence is best - thus, even if we don't accept the judgement of the medical examiners of the time, their statements are still our evidence, and can therefore be considered (even if ultimately discarded).

Furtherfurthermore, even though I do not believe one can trust their judgement (because we now know that it is not possible to be certain), the fact that they believed that they could, in fact, determine probable handedness, is in itself of some interest, for instance to historians of forensics. That might belong in another thread, of course, but it's possible that Pierre has this aspect in mind.

Dear Kattrup

There is of course plenty of evidence which one could work from, my point was that some, appeared from their comments, not to have read Biggs comments.

Your comment that both Mr Marriott and myself may not have read the comments by Briggs is utterly ridiculous, do you know the history of those comments from Dr Biggs?
Kattrup your reply in places comes across as unnecessary confrontational, there is no need for that.

If you felt a need to respond to my post then all you needed to say, was something like "yes I have read them, but ................."
That would have been the end, quick and sweet.
yours


Steve

[Kattrup]

In post #3 Mr Trevor Marriott posted comments from Dr Biggs which made it clear that a definitive answer cannot be obtained on this issue....
[...] please at least give some indication that you have read the comments he made; otherwise this may as well be a different thread.

regards

Steve

Well, I've of course read the thread and Trevor Marriot's overly curt insistence that further debate is pointless.

You seem to accept his stance.

A fair question might be has he, or have you, read Dr. Biggs' statement?

The expert pathologist states that it is not considered possible from the appearance of the wounds to determine whether it was caused by a left- or righthanded man.

This is, I believe, uncontroversial in today's forensics. It only means, however, that once the body is taken away, wounds washed, studying the wound itself will not reveal from which direction it was inflicted.

It does not mean that no other evidence should be taken into consideration, nor that it is impossible to infer whether the culprit was most likely right- or lefthanded.
A right-handed man attacking another from the front will inflict the majority of the wounds on the left side of the victim. Of course, a left-handed man attacking from the left side of the victim will too. So there are other types of evidence than merely analysing the appearance of the wounds (also blood splatter patterns could be analysed).

As stated, I believe that the sources describing the victims, the locations of their wounds and the crime scenes give indications as to the killer's handedness. This does not conflict with the learned Dr. Biggs' statement.

Furthermore, this thread is about which evidence is best - thus, even if we don't accept the judgement of the medical examiners of the time, their statements are still our evidence, and can therefore be considered (even if ultimately discarded).

Furtherfurthermore, even though I do not believe one can trust their judgement (because we now know that it is not possible to be certain), the fact that they believed that they could, in fact, determine probable handedness, is in itself of some interest, for instance to historians of forensics. That might belong in another thread, of course, but it's possible that Pierre has this aspect in mind.

[Robert St Devil]

Hello Pierre.

Best evidence may come from the Polly Nicholls murder, and how you interpret her injuries. It's possible that 2... maybe 3... of her injuries happened in conjunction.

I don't remember Polly being strangled with a neckerchief. Instead, I'm thinking the bruises on either side of her face indicate that Jack the Ripper's right hand was silencing her. Bruising would have occurred prior to her death. He was brutally covering her mouth and nose. Last year, it was pointed out to me that there may be evidence of her nose being "broken" based on its appearance in her morgue photo.
Next, she has a stab wound on the right side of her abdomen that is described as running in a downwards position.

Putting this together, it could be that he covered her mouth with his right hand while stabbing her with his left.

[Elamarna]

In post #3 Mr Trevor Marriott posted comments from Dr Biggs which made it clear that a definitive answer cannot be obtained on this issue.

When Pierre asked if Biggs had done any research on the subject Mr Marriott replied with the statement:

"Dr Biggs is a forensic pathologist. He speaks from knowledge and experience in assisting in the investigation of murders etc."


It appeared that this was accepted, as no further comments were made at that stage.

Now of course everyone is free to comment on this thread, such debate is always healthy, but from some of the recent posts it seems not all are bothering to read the first 12 posts on the thread, a point already raised by John G.
By all means disagree with Dr Biggs, after all it is only the opinion of one man, an expert in forensic pathology; but please at least give some indication that you have read the comments he made; otherwise this may as well be a different thread.

regards

Steve

[Pierre]

Double posted.