Luke's DNA

[Chris_Halkides]

Thompson, William C., Law, Probability and Risk (2009) 8, 257−276. doi:10.1093/lpr/mgp013
"Painting the target around the matching profile: the Texas sharpshooter fallacy in forensic DNA interpretation"

A portion of the abstract:  "Using examples from casework, informal and naturalistic experiments, and analysts’ own testimony, this article demonstrates how post hoc target shifting occurs and how it can distort the frequency and likelihood ratio statistics used to characterize DNA matches, making matches appear more probative than they actually are."

This article has an excellent discussion of how subjectivity and bias can creep into DNA forensics, particularly where DNA mixtures are concerned.  Although some knowledge of DNA profiling is helpful, even without it, a reader can pick up on some of the problems, starting on p. 261.

In the context of the present case, I would like to make two points.  One, Susan Ure did not say that Luke Mitchell was "included" as a possible donor.  IMO the language is important.  Two, even if she had, Professor Thompson's article demonstrates that target shifting can broaden the scope of who is included.

[Chris_Halkides]

[Is the lack of Luke Mitchell's DNA] correct, as that seems to be the main thing the innocent group seems to go on about but i thought this had already been disproved?

Your premise is mistaken: the people who question the safety of this conviction do so for a variety of reasons, such as the problematic eyewitness accounts or the existence of other forensic evidence pointing to other suspects.  We probably should move to a separate thread or start a new one if we wish to explore this further.

There is another issue in your post that is worth addressing, which concerns the fact that Luke and Jodie were in a relationship.  A DNA profile that can be tied to a particular body fluid stain (source DNA) is more valuable as evidence that DNA that cannot be (sub-source DNA).  This is speculation, but the DNA on the bra might not have had an identified body fluid source.  The profile on Luke's trousers was probably sub-source, although there were other reasons to discard this as an evidentiary lead.

[Mr Apples]

What I would like clarification on is quite simple: to this day, as far as I’m aware, there are profiles from 5 males that remain ‘unidentified’ (among them is a full profile from a condom found in a cave used by vagrants, near the locus, and NOT the condom belonging to JAMF). So, how could CD proclaim that ‘there were no dna results that could be unaccounted for’?  Am I missing something glaringly obvious? Unidentified is self-explanatory? I get that the likelihood of this being carried out by a random stranger is extremely slim, but it’s perhaps still worthy of consideration.  Page 205 from IB speculates on these 5 unidentified male profiles, btw.

[faithlilly]

What I would like clarification on is quite simple: to this day, as far as I’m aware, there are profiles from 5 males that remain ‘unidentified’ (among them is a full profile from a condom found in a cave used by vagrants, near the locus, and NOT the condom belonging to JAMF). So, how could CD proclaim that ‘there were no dna results that could be unaccounted for’?  Am I missing something glaringly obvious? Unidentified is self-explanatory? I get that the likelihood of this being carried out by a random stranger is extremely slim, but it’s perhaps still worthy of consideration.  Page 205 from IB speculates on these 5 unidentified male profiles, btw.

‘ I get that the likelihood of this being carried out by a random stranger is extremely slim’

Could you please explain your reasoning?

[Parky41]

Ok - condoms, who would have thought eh? Woodlands and caves within said woodlands. The reality, that the only thing relevant in placing any question mark upon 'unidentified male profiles' is to do with the victim/clothing and immediate locality of said crime. And what we are left with is one, that is one profile.

This from a sperm head on the shoe of the victim. The victim who had firstly been walking in this strip of woodland with her boyfriend then running from him. A strip of woodland with numerous condoms and left overs from many a courting couple and the likes. She picked up a singular sperm head through trace transferral.

JaF - Fresh and known to have therefore been deposited in recent hours. Wrong time and place nothing more nor sinister. The condom in a cave some distance away, in another stretch of woodland.  Around 1/2 a mile if using the Esk Trail or 1/4 as the crow flies. Numerous items tested as there had been reports of vagrants sleeping in the 'actual Abbey woods'. The vagrants needed traced and eliminated. The condom from some male discarded after having intercourse out of prying eyes from passers by. To note her, not just a male profile but that of the female he had intercourse with - that female not being the victim. As with JaF no female DNA as he had his jollies with himself. Are we here to judge that, people have many forms of sexual activities in woodland. All with that risk, buzz even for some of being caught!

This claimed other two unidentified profiles - well going by the above we can bet they are of the exact same worth = nada, zilch, nothing. The very reason therefore why CD could come out with 'nothing unaccounted for'

To do directly with the victim/clothing and so forth there were two clear donors of DNA - one SK and of course the other LM. These were the two males with trace/transferral/rainwater diffusion applicable directly. SK as we know via the top the victim was wearing of her sister and of course Mitchell due to the intimate relationship with the victim and mainly upon her underwear. 

The profiles/partial and otherwise obtained were enough for the police to believe a warrant would be issued for Mitchells arrest in the August, the Crown turning it down. They were not going to be able to use Mitchells DNA for that very reason, there was nothing to show that it could not have been there prior to the murder itself. The only DNA that could have been used was something upon Mitchell (blood of the victim) and something of the attacker from the victim (fingernail scrapings), there was nothing. That is nothing of anyone. And is exactly the reason why the agreement was made to stop short of going through all of the DNA applicable to Mitchell. An endless pointless exercise of time consumption with nothing to show. The very reason the Crown built their case around circumstantial evidence.

To note here = Nothing from the defence, that is zilch from this crime, for them to use to point forensic evidence towards A another/stranger murder - nothing. Bar SK to cast doubt in the Jurors mind. Of course they as did the court, got to hear of Kelly's alibi from his father and girlfriend and the experts advice on the transferral of his DNA from said t-shirt. But of course the author did not attend the trial, did she? I mean, she did not even know that one of the key witnesses testified, said witness being AO.

Yet, as many others have pointed out, one really had to be part of that vital area of proceedings, to get a feel of the case and the evidence presented before the court. Then and only then could they give sound and proper judgement of the case against Mitchell and one of his defence. Yet here we have an author who has written on this case, not once but twice, put it to social media and TV productions -  Was not privy to the investigation side, was not privy to hearing the case first hand, goes solely upon the defence papers handed down from DF, media reports and the the WORD of a convicted murderer? - and that judgement is to be trusted?

So what one does do, is harp on about sperm/semen/condoms and unidentified profiles, narrowed down to five now over the years. And it gets results, it hits the spot for those with little upstairs and they make comments such as "there was five o them there wi cotter as the lookout"

What the court heard, that Jury was all of the forensic evidence. There was no rape, no sexual physical assault. No sperm/semen/condoms to do with the murder at all. Nothing. So this condom in a cave in another stretch of woodland entirely, with two unidentified profiles both male and female, has what exactly to do with the murder of this young girl?

[Mr Apples]

‘ I get that the likelihood of this being carried out by a random stranger is extremely slim’

Could you please explain your reasoning?

The killer invariably knows the victim; randomness in murder is very rare. Dalkeith is a relatively small town, and despite its near proximity to Scotland’s capital city, I very much doubt someone cherry-picked Dalkeith as a place to abduct and kill a stranger. Lastly, the location where the deceased’s body was found would suggest that it was someone who knew the area very well; the body lay undiscovered for some 6 hours before it was found, despite it being a popular area for youths, walkers and dog walkers. Where the body lay — in undergrowth in a woodland strip (nearer to N’battle than E’houses) behind a 7-8ft stone dyke — was indicative of someone who had intimate knowledge of the locus and general area.

[Rusty]

The killer invariably knows the victim; randomness in murder is very rare. Dalkeith is a relatively small town, and despite its near proximity to Scotland’s capital city, I very much doubt someone cherry-picked Dalkeith as a place to abduct and kill a stranger. Lastly, the location where the deceased’s body was found would suggest that it was someone who knew the area very well; the body lay undiscovered for some 6 hours before it was found, despite it being a popular area for youths, walkers and dog walkers. Where the body lay — in undergrowth in a woodland strip (nearer to N’battle than E’houses) behind a 7-8ft stone dyke — was indicative of someone who had intimate knowledge of the locus and general area.

Aye. His name was Luke Mitchell.

[Mr Apples]

Aye. His name was Luke Mitchell.

I’m about 98% sure it was Luke who did it. Btw, Rusty, are you from near the area where this happened? Have you been following the case long?

[Mr Apples]

Ok - condoms, who would have thought eh? Woodlands and caves within said woodlands. The reality, that the only thing relevant in placing any question mark upon 'unidentified male profiles' is to do with the victim/clothing and immediate locality of said crime. And what we are left with is one, that is one profile.

This from a sperm head on the shoe of the victim. The victim who had firstly been walking in this strip of woodland with her boyfriend then running from him. A strip of woodland with numerous condoms and left overs from many a courting couple and the likes. She picked up a singular sperm head through trace transferral.

JaF - Fresh and known to have therefore been deposited in recent hours. Wrong time and place nothing more nor sinister. The condom in a cave some distance away, in another stretch of woodland.  Around 1/2 a mile if using the Esk Trail or 1/4 as the crow flies. Numerous items tested as there had been reports of vagrants sleeping in the 'actual Abbey woods'. The vagrants needed traced and eliminated. The condom from some male discarded after having intercourse out of prying eyes from passers by. To note her, not just a male profile but that of the female he had intercourse with - that female not being the victim. As with JaF no female DNA as he had his jollies with himself. Are we here to judge that, people have many forms of sexual activities in woodland. All with that risk, buzz even for some of being caught!

This claimed other two unidentified profiles - well going by the above we can bet they are of the exact same worth = nada, zilch, nothing. The very reason therefore why CD could come out with 'nothing unaccounted for'

To do directly with the victim/clothing and so forth there were two clear donors of DNA - one SK and of course the other LM. These were the two males with trace/transferral/rainwater diffusion applicable directly. SK as we know via the top the victim was wearing of her sister and of course Mitchell due to the intimate relationship with the victim and mainly upon her underwear. 

The profiles/partial and otherwise obtained were enough for the police to believe a warrant would be issued for Mitchells arrest in the August, the Crown turning it down. They were not going to be able to use Mitchells DNA for that very reason, there was nothing to show that it could not have been there prior to the murder itself. The only DNA that could have been used was something upon Mitchell (blood of the victim) and something of the attacker from the victim (fingernail scrapings), there was nothing. That is nothing of anyone. And is exactly the reason why the agreement was made to stop short of going through all of the DNA applicable to Mitchell. An endless pointless exercise of time consumption with nothing to show. The very reason the Crown built their case around circumstantial evidence.

To note here = Nothing from the defence, that is zilch from this crime, for them to use to point forensic evidence towards A another/stranger murder - nothing. Bar SK to cast doubt in the Jurors mind. Of course they as did the court, got to hear of Kelly's alibi from his father and girlfriend and the experts advice on the transferral of his DNA from said t-shirt. But of course the author did not attend the trial, did she? I mean, she did not even know that one of the key witnesses testified, said witness being AO.

Yet, as many others have pointed out, one really had to be part of that vital area of proceedings, to get a feel of the case and the evidence presented before the court. Then and only then could they give sound and proper judgement of the case against Mitchell and one of his defence. Yet here we have an author who has written on this case, not once but twice, put it to social media and TV productions -  Was not privy to the investigation side, was not privy to hearing the case first hand, goes solely upon the defence papers handed down from DF, media reports and the the WORD of a convicted murderer? - and that judgement is to be trusted?

So what one does do, is harp on about sperm/semen/condoms and unidentified profiles, narrowed down to five now over the years. And it gets results, it hits the spot for those with little upstairs and they make comments such as "there was five o them there wi cotter as the lookout"

What the court heard, that Jury was all of the forensic evidence. There was no rape, no sexual physical assault. No sperm/semen/condoms to do with the murder at all. Nothing. So this condom in a cave in another stretch of woodland entirely, with two unidentified profiles both male and female, has what exactly to do with the murder of this young girl?

Sorry, Parky41 — I had forgotten all about this. Thanks for the reply. Yeah, the vagrant (s) was traced and eliminated (SL doesn’t make it clear in IB that the cave is some distance away from the locus). LM’s DNA was found on Jodi’s underwear?? I thought only partial profiles of LM were found on her bra? Do you have a cite for this?

Is the general consensus here that LM, as a direct result of a mismanaged crime scene (i.e., the body being left exposed to the rain and elements all morning, the body being moved and Jodi’s clothing being gathered up and bundled on top of each other), got lucky? That the crime scene mismanagement resulted in degraded and contaminated DNA that worked in LM’s favour? That any dna marker or partial dna profile of LM’s obtained means that he probably did do it? Such is your entrenched belief he is guilty?

[Chris_Halkides]

It is my opinion that the crime scene was indeed badly mismanaged.  Given this and other professional lapses, I would like to see an independent review of the DNA data.

[Mr Apples]

The following is a paragraph from IB (p.200), verbatim:

”Another surprising aspect of the forensic evidence in this case was the sheer number of samples which came back from the labs labelled “no reportable result”. A person of interest to the enquiry (not Luke) was found to have blood stains on his jacket and trainers and blood was found on the blade, handle and sheath of a knife belonging to him. The knife blade was 153 mm long and 16 mm wide (around 6.5 inches long and 3/4 inch wide). Every sample pertaining to this person was on the 121 item “no reportable result” list.”

Interesting. Anyone know who this person was? JOSJ? JF?

[Mr Apples]

It is my opinion that the crime scene was indeed badly mismanaged.  Given this and other professional lapses, I would like to see an independent review of the DNA data.

Chris, regardless of an independent review or LM having suffered a miscarriage of justice at the original trial, do you still think it’s highly probable that Luke did it? Or do you think someone else was responsible for Jodi’s murder? I think the police had to use unorthodox tactics during their investigation to go toe-to-toe with an advanced, intelligent, sophisticated and devious teenager. They knew it was him from the first few weeks and were absolutely certain by the 14.04.04. This, imo, is why they tried to use underhand means to get him to confess rather than try and convict him on circumstantial evidence . . . the latter is much more difficult to prove in a court of law. And I’m not suggesting the police’s aim was to elicit a false confession from Luke, as that would be unethical and a level that I’m sure L&B Police would not stoop to. So, no, no fit up, no desperation from the police to get a quick conviction on the back of public outcry, or morally wrong tactics utilised to convict an innocent teenager — just a police force that was forced to fight fire with fire in a horrific and unique case, so as to get justice. Some people keep saying LM was only a child, but, he was not. He was a deeply troubled and disturbed teenager, and a highly intelligent, sophisticated, devious and manipulative one at that.

[Rusty]

I’m about 98% sure it was Luke who did it. Btw, Rusty, are you from near the area where this happened? Have you been following the case long?

Close enough.

Aye, since the old WAP days. I got binned from there. The vendetta against the Jones's, by the 2 clowns that ran the place, was stomach churning to say the least.

[Chris_Halkides]

Chris, regardless of an independent review or LM having suffered a miscarriage of justice at the original trial, do you still think it’s highly probable that Luke did it? Or do you think someone else was responsible for Jodi’s murder? I think the police had to use unorthodox tactics during their investigation to go toe-to-toe with an advanced, intelligent, sophisticated and devious teenager. They knew it was him from the first few weeks and were absolutely certain by the 14.04.04. This, imo, is why they tried to use underhand means to get him to confess rather than try and convict him on circumstantial evidence . . . the latter is much more difficult to prove in a court of law. And I’m not suggesting the police’s aim was to elicit a false confession from Luke, as that would be unethical and a level that I’m sure L&B Police would not stoop to. So, no, no fit up, no desperation from the police to get a quick conviction on the back of public outcry, or morally wrong tactics utilised to convict an innocent teenager — just a police force that was forced to fight fire with fire in a horrific and unique case, so as to get justice. Some people keep saying LM was only a child, but, he was not. He was a deeply troubled and disturbed teenager, and a highly intelligent, sophisticated, devious and manipulative one at that.

These are very separate questions.  One cannot go back in time and fix a mismanaged crime scene; therefore, it will always be more difficult to convict someone than it should have been.  The other problem at work in this instance is drawing a conclusion too early.  If the police believed that Luke were guilty early on and that the case were unique, then the likelihood of their doing or failing to do things which bias the investigation toward finding him guilty.  Bias can either be conscious or unconscious, and the history of forensics is littered with examples in which the forensic investigation bent itself toward the conclusions favored by the police.  That is why I favor an independent review of the DNA forensics (possibly modeled on how Australia conducted reviews of the DNA evidence in Farah Jama case or in the Jaidyn Leskie case), and I would support a broader review of the present case.

I don't hold a strong opinion as to who committed this murder.  I do have grave concerns about many aspects of this investigation.  One of my reasons for concern is the witness testimony.  Those interested may look elsewhere on the internet for posts by Rolfe about the testimony of Andrina Bryson. 

[Parky41]

Decided to put the post into several smaller bullet points:

If there had been none and no further DNA of Mitchells present then there would have been no agreement, that is simple logic.

The agreement did take place, SL knows it took place, she gives reference to it from "source's"  It highlights one thing yet again, that of not attending Mitchells trial, or least no admittance/denial of this. There can be no denying that it pays to play dumb around vital evidence/information. When bias is the motive.

Logic and sense please. Really is one of those "No Shit Sherlock" moments. The agreement was NOT around forensics/DNA in general. It was specific to the presence of Mitchells DNA. As above, none and no more then simply no agreement, and that agreement took place.

"There was no forensic evidence found upon my client linking him to the murder" / "There was none of Luke's DNA found directly linked to the murder (DF/SL)

  Is the exact same as, there was no incriminating DNA, upon Mitchell, his home or upon the victims clothing/body. Not that there was none present, simply that there was NO incriminating DNA. Nothing that could not be explained by way of innocent transfer, from their relationship, their time spent together that same day at school. From any previous encounter. = Circumstantial case.

These 'source's' that SL mentions - DF and the Crown? Who got to hear this agreement first hand? LM that is who. And there is, no, he simply did not hear, he may have picked it up wrong. Those daily briefs, the days proceedings explained in full, and no doubt endless questions from Mitchell himself.

SL states that she does NOT know the details of this agreement, yet applies that it was simply made around forensics/DNA in general? That information relating to it is missing from the defence papers? It is areas such as this that never fail to amaze me. In that people do not pick up what is blatantly obvious, there should be no ? placed upon the agreement with that pretence of not knowing why it was made? - You are being spun a yarn, are you not? For;

In this chain of events, between three people, there is dishonesty, hiding the truth. There is no way around this. We know from the way in which things are written, that discussion took place between Mitchell, his mother and SL, discussion of this agreement. She tells us this. She states that a 'source' informed them. If she is being honest, that she does not know the details of the agreement, then LM and his mother have not been honest with her, they have been hiding vital information. And if they have been hiding information, it is simply because they have something to hide. What exactly did they say to her? 'We know, a source told us, but we are keeping the reason for the agreement to ourselves?' - are people really that naive? Flip that over, if they were honest and told her the reason for the agreement, the details, then it is SL who is not being forthright, and showing how easily one can simply manipulate around the truth?

It however does bulk up the pages of the book, does it not, this waffle around irrelevant matters. It does not take pages to explain that the case was circumstantial. If one needs to go to extraordinary lengths to show people, rather than a simple definition, then does this tell us what type of mindset one is aiming at to convince - to pull the wool over? with blatant supposition?

And of course, last but by no means least. Why? What possible reason could there be for playing dumb around why the agreement was made? We know the presence of Mitchells DNA is irrelevant, the very reason why the evidence was circumstantial.  Two clear donors, only one to explain in full why the presence of his DNA was there, SK of course. And yawn and yes, it is still a long post. There was no stranger DNA, nothing left from some 'other' murderer.

There is no, LM managed to clean the scene completely of his whilst leaving DNA of others there - Going to stop there, the realms entered into with someone hiding the actual truth, really does work. This soaking it up, churning it round and spitting it back out with additives.  With this 'we will never know'

SL was unhappy with the report back from the SCCRC, asked of the testing carried out by them? That they did not carry out as much testing as hoped for? Well, one is not going to be re testing for the DNA of LM nor SK, are they? They did carry out further tests and there was still nothing pointing this murder elsewhere. Why would there be, the murderer is in jail.

But as always and by invitation, we are all free to 'make of it what we will' - No stranger DNA, no 'we will never know' - but above all, and it is highly relevant, is that massive conflict of interest. Three people together for at least 8 months prior to Mitchells arrest. If one has not been honest around multiple areas since his trial, does one really believe there was honesty before it, before his arrest? Just short of that time he was out celebrating the 'end of a difficult time'

LM was proven to be intelligent and a compulsive liar - There is no doubt in this. And yes we can apply many reasons. Just a lad, they all lie. Worried about being incriminated in some way. Fair enough, but this does not mean he was simply honest at any other time, does it. And as above. - this is not based upon honesty, it is based upon hiding the truth?