A6 Murder DNA evidence

[JamesDean]

No it isn't. It is vital. Every schoolchild is taught in science that you first work out what you expect to find, and then to compare what you expect to get with what you actually get, and in most cases give a %age yield.

In this case you expect to find DNA profiles from VS, the rapist, possibly MG and maybe some of the investigators\technicians and other contaminants (including JH).

I have no problem with expecting (or hoping) to find DNA profiles. The point I was making originally is that it is a false assumption that any DNA profiles must have originated from semen. To do so eliminates the possibility of contamination from any other type of genetic material. I don't accept that as reasonable.

[Victor]

Tut tut! You are attributing that quote to me and it is simply a reversal of what Caz said.

I appreciate that it is a reversal of Caz, but it was included in your post and is the only place where I could copy and quote it from.

[Victor]

I have no problem with expecting (or hoping) to find DNA profiles. The point I was making originally is that it is a false assumption that any DNA profiles must have originated from semen. To do so eliminates the possibility of contamination from any other type of genetic material. I don't accept that as reasonable.

That is the issue, the expectation was to find the DNA of the rapist and victim from the semen and vaginal fluids, therefore what has happened to the DNA from the rapists' semen?

Without the raw data it is impossible to say whether any semen was microscopically visually identified, and it may be for this reason that they concluded that the contaminant had to be semen.

[JamesDean]

That is the issue, the expectation was to find the DNA of the rapist and victim from the semen and vaginal fluids

No you are leaping ahead again and still assuming that any male DNA found is from semen. That may have been the expectation but once the process of extracting and amplifying of DNA is underway there is no way of knowing what type of genetic material was the source of the base DNA.

..... therefore what has happened to the DNA from the rapists' semen?

That is an entirely separate issue unrelated to whether or not contamination has to be semen.

[Victor]

No you are leaping ahead again and still assuming that any male DNA found is from semen. That may have been the expectation but once the process of extracting and amplifying of DNA is underway there is no way of knowing what type of genetic material was the source of the base DNA.

I was starting from the expectation that a piece of semen stained knickers would give DNA profiles of the semen and vaginal fluids.

Then from there we have the results of a DNA profile from VS and MG which are assumed to come from the semen and vaginal fluids - and it this assumption that you are challenging. Which of course ties back to the questions of whether MG's profile was positively identified.

In other words you are saying that none of the DNA profiles came from the sample because they had degraded and that all 3 of the detected profiles are contamination. This I can follow logically, however it does depend on whether anything was visible microscopically which we are not told.

It can be inferred that because Dr Evison "seemed to" accept that any contamination was semen that this argument was pursued, hence your challenge of this part.

That is an entirely separate issue unrelated to whether or not contamination has to be semen.

Not entirely separate because of the need to assume that the DNA profile from the semen has degraded and is undetectable.

[caz]

Hi James,

The reversal of Caz doesn’t quite work, because I had no opinion on whether or not Hanratty was guilty based on the original case evidence. It's when I take the DNA findings and the appeal judgement into account and look again at the available evidence as a whole that it does 'add up' for me that he was the rapist and murderer and not Alphon or anyone else. It also reduces what others are still describing as some huge 'mystery' to a matter of some remarkable coincidences (which you tend to find in high-profile cases anyway for some reason) and a few questions concerning other people's behaviour, such as whether anyone knew Hanratty did it, and planted the gun and hankie to help the police get their man.

There is another crucial difference: the DNA evidence doesn’t have to be conclusive, reliable or admissible in order for the conclusion to be the right one. The reverse could not be more different, because in order for the conclusion to be wrong, the DNA evidence has to be flawed, and to a pretty extreme degree. It would involve the knickers in a series of mishaps bordering on the farcical: Dr Grant managing to cut a fragment with no O group semen present from the rapist himself, but which 40 years later produces not just the AB group male DNA expected if MG’s semen was present, but also the O group DNA from the convicted man, which is supposed to have only found its way by accident onto that same small fragment; and finally everyone involved with the appeal mistakenly believing, or at least being persuaded to accept, that there was no realistic possibility of anything of the sort having happened, despite all the caveats in the world about evidence being mishandled back in the dark ages of the 1960s.

Maybe I’m being extra dense today, but I can’t see from your other response to me whether you quite appreciated what I was getting at, so I’ll have another bash and rephrase the question:

1) Is there any suggestion that sperm heads were looked for or found on VS's knicker fragment?

2) Should sperm heads still be detectable after 40 years, and should some have been confirmed present on the fragment before the conclusion was reached that the two male DNA profiles obtained were ‘specifically’ from sperm?

Come on, I’m trying to find a loophole for you here. If they tried and failed to find any sperm heads, unlike the Castree case, would it be clear evidence that JH's DNA did not come from his semen and that the other male DNA (AB blood group) did not come from MG's semen either?

Conversely, if sperm heads were indeed found, can we be sure that nothing else could have been observed that was consistent with the two semen deposits on the knickers in 1961?

Love,

Caz
X

[reg1965]

Hi James,

The reversal of Caz doesn’t quite work, because I had no opinion on whether or not Hanratty was guilty based on the original case evidence. It's when I take the DNA findings and the appeal judgement into account and look again at the available evidence as a whole that it does 'add up' for me that he was the rapist and murderer and not Alphon or anyone else. It also reduces what others are still describing as some huge 'mystery' to a matter of some remarkable coincidences (which you tend to find in high-profile cases anyway for some reason) and a few questions concerning other people's behaviour, such as whether anyone knew Hanratty did it, and planted the gun and hankie to help the police get their man.

There is another crucial difference: the DNA evidence doesn’t have to be conclusive, reliable or admissible in order for the conclusion to be the right one. The reverse could not be more different, because in order for the conclusion to be wrong, the DNA evidence has to be flawed, and to a pretty extreme degree. It would involve the knickers in a series of mishaps bordering on the farcical: Dr Grant managing to cut a fragment with no O group semen present from the rapist himself, but which 40 years later produces not just the AB group male DNA expected if MG’s semen was present, but also the O group DNA from the convicted man, which is supposed to have only found its way by accident onto that same small fragment; and finally everyone involved with the appeal mistakenly believing, or at least being persuaded to accept, that there was no realistic possibility of anything of the sort having happened, despite all the caveats in the world about evidence being mishandled back in the dark ages of the 1960s.

Maybe I’m being extra dense today, but I can’t see from your other response to me whether you quite appreciated what I was getting at, so I’ll have another bash and rephrase the question:

1) Is there any suggestion that sperm heads were looked for or found on VS's knicker fragment?

2) Should sperm heads still be detectable after 40 years, and should some have been confirmed present on the fragment before the conclusion was reached that the two male DNA profiles obtained were ‘specifically’ from sperm?

Come on, I’m trying to find a loophole for you here. If they tried and failed to find any sperm heads, unlike the Castree case, would it be clear evidence that JH's DNA did not come from his semen and that the other male DNA (AB blood group) did not come from MG's semen either?

Conversely, if sperm heads were indeed found, can we be sure that nothing else could have been observed that was consistent with the two semen deposits on the knickers in 1961?

Love,

Caz
X

Hi Caz
Re my post #58
I would like to apologise unconditionally for what I said, which was extremely harsh to say the least and I have no excuses. I hope that you accept my apology and that we can move on.

Re your post above
I am not sure what you mean by conclusion in the second paragraph. Besides, why was the LCN DNA technique needed. Traditional methods such as SGM+ had not detected conclusive profiles? The original evidential bodily fluids and tissue had degraded to a degree where only microsopic pieces of useful DNA where left, hence the use of LCN.

Kind regards
Reg

[JamesDean]

Maybe I’m being extra dense today, but I can’t see from your other response to me whether you quite appreciated what I was getting at, so I’ll have another bash and rephrase the question:

1) Is there any suggestion that sperm heads were looked for or found on VS's knicker fragment?

2) Should sperm heads still be detectable after 40 years, and should some have been confirmed present on the fragment before the conclusion was reached that the two male DNA profiles obtained were ‘specifically’ from sperm?

Come on, I’m trying to find a loophole for you here. If they tried and failed to find any sperm heads, unlike the Castree case, would it be clear evidence that JH's DNA did not come from his semen and that the other male DNA (AB blood group) did not come from MG's semen either?

Conversely, if sperm heads were indeed found, can we be sure that nothing else could have been observed that was consistent with the two semen deposits on the knickers in 1961?

Love,

Caz
X

Morning Caz,

There is no suggestion that 'sperm heads' were looked for on the fragment. Sperm degenerates very quickly; 48 hours is a long time according to a FBI forensic website; 40 years is inconceivable! That anything testable survived the passage of time was a miracle in itself.

You have yourself stated your disbelief at any suggestion that the fragment may not have the rapist' DNA on it (Houdini, magical disappearing DNA etc) so why should the FSS take the trouble to ascertain that the fragment did indeed have sperm on it? Why not presume, as you do, that a semen stain probably contains sperm? In any event, it is not possible to identify sperm from different individuals visually if they are mixed together. DNA tests can reveal mixed profiles ... but is the DNA from sperm alone?

The fragment was small and was further divided, part of it tested in 1995 with no result and the remainder in 1997 when profiles were, ostensibly, obtained. Who knows what was assumed during the testing but we do know from the judgment that there was a presumption that the male profiles were both obtained from semen. This presumption was the basis of the theory that contamination was a remote possibility.

In my opinion it was an error of judgment (pun intended) to presume that contamination had to be from semen. That presumption is the device by which the prosecution contends that there was no likely mechanism for contamination to occur. Dr Evison, for the defence, never accepted that contamination was highly unlikely. How do I know that? It says so in the judgment!

121. That said we should also record that not one of the respondent’s witnesses
excluded the possibility of contamination. They have expressed themselves in
different ways but the general tenor of the evidence has been that they each
considered the possibility to be remote. That, of course, has to be contrasted
with the opinion of Dr Evison who never moved from his original position as
stated in this judgment.

Love
James
x

[Victor]

Morning Caz,

There is no suggestion that 'sperm heads' were looked for on the fragment. Sperm degenerates very quickly; 48 hours is a long time according to a FBI forensic website; 40 years is inconceivable! That anything testable survived the passage of time was a miracle in itself.

Hi James,

In the Castree case that Caz quoted from the documentary last monday night on ITV1 sperm heads were microscopically detected and a DNA profile obtained from them 16 YEARS later. I appreciate that it's a jump from 16 years to 40 years, but it's several orders of magnitude less than the jump from 48hours to 16 years.

You have yourself stated your disbelief at any suggestion that the fragment may not have the rapist' DNA on it (Houdini, magical disappearing DNA etc) so why should the FSS take the trouble to ascertain that the fragment did indeed have sperm on it? Why not presume, as you do, that a semen stain probably contains sperm? In any event, it is not possible to identify sperm from different individuals visually if they are mixed together. DNA tests can reveal mixed profiles ... but is the DNA from sperm alone?

We are not trying to identify sperm from different individuals, we are trying to ascertain whether there was any visible sperm heads. And I agree with your last question... is the DNA from sperm alone? [Obviously not for VS]

The fragment was small and was further divided, part of it tested in 1995 with no result and the remainder in 1997 when profiles were, ostensibly, obtained. Who knows what was assumed during the testing but we do know from the judgment that there was a presumption that the male profiles were both obtained from semen. This presumption was the basis of the theory that contamination was a remote possibility.

In my opinion it was an error of judgment (pun intended) to presume that contamination had to be from semen. That presumption is the device by which the prosecution contends that there was no likely mechanism for contamination to occur. Dr Evison, for the defence, never accepted that contamination was highly unlikely. How do I know that? It says so in the judgment!

Love
James
x

So why are you prepared to accept the judgment when it says Dr Evison didn't accept that contamination was highly unlikely, but not accept that he "seemed to" accept that contamination would have to be semen?

KR,
Vic.

[JamesDean]

In the Castree case that Caz quoted from the documentary last monday night on ITV1 sperm heads were microscopically detected and a DNA profile obtained from them 16 YEARS later. I appreciate that it's a jump from 16 years to 40 years, but it's several orders of magnitude less than the jump from 48hours to 16 years.

The method of collection and storage of DNA evidence is a crucial factor in determining how long the evidence will remain useful. In non-ideal conditions of collection and storage, DNA degrades rapidly. Yes I agree that years or decades are of a different order of magnitude to hours. That is simply a comparison between an ideal timescale for properly storing DNA evidence and a random timescale where, by chance, the DNA survived to an extent that it was still useful. That does not imply that DNA evidence will survive for years or decades only that it may do so. I would suggest that the length of time that the sperm heads survived in the Castree case has no bearing at all on how long the DNA on the knicker fragment would survive as the methods of collection and storage in the two cases was not identical in any way. The only similarity between the Castree DNA and the Hanratty DNA is that the remnants of DNA in both cases are both rather old.

Degradation is problematic:

Degradation of DNA

While techniques for preserving DNA samples have improved over the years, DNA cannot be maintained indefinitely. The actual rate at which a DNA sample degrades varies depending on: 1) cell type; 2) the amount of DNA present; and 3) the conditions under which it is preserved. But even under optimal conditions, DNA will continuously degrade over time.

Biological samples that are even partly degraded are difficult to type, and attempts to do so are more prone to certain errors. Significant degradation will produce ""inconclusive"" results in DNA testing.

We are not trying to identify sperm from different individuals, we are trying to ascertain whether there was any visible sperm heads.

Identifying intact sperm heads would not indicate if the sperm was from one donor or two. If two male profiles are found we cannot be certain that both profiles came from DNA in sperm heads or other cell types. We don't even know if either male profile was derived from sperm head DNA but the judgment presumed it was. That presumption was the basis of the assumption that contamination was possible but only a remote possibility.

So why are you prepared to accept the judgment when it says Dr Evison didn't accept that contamination was highly unlikely, but not accept that he "seemed to" accept that contamination would have to be semen?

I did accept that the judgment says that Dr Evison seemed to accept that contamination would have to be semen. The judgment quite clearly does say that. I'm saying that's a subjective statement not a statement of fact, as implied by usage of the word seemed.

Regards
James

[Victor]

The method of collection and storage of DNA evidence is a crucial factor in determining how long the evidence will remain useful. In non-ideal conditions of collection and storage, DNA degrades rapidly. Yes I agree that years or decades are of a different order of magnitude to hours. That is simply a comparison between an ideal timescale for properly storing DNA evidence and a random timescale where, by chance, the DNA survived to an extent that it was still useful. That does not imply that DNA evidence will survive for years or decades only that it may do so. I would suggest that the length of time that the sperm heads survived in the Castree case has no bearing at all on how long the DNA on the knicker fragment would survive as the methods of collection and storage in the two cases was not identical in any way. The only similarity between the Castree DNA and the Hanratty DNA is that the remnants of DNA in both cases are both rather old.

Yes I accept that DNA degrades over time, with lots of different factors. In the castree case the sperm heads were collected on sticky tape that had been passed over the victim's clothing. But your last sentence I strongly disagree with, for example, 1. the DNA in both cases is believed to be semen, 2. taken from the victim's clothing, 3. as you say both samples are rather old, 4. most of the evidence was destroyed leaving only a small sample to work from. In fact there are very few dissimilarities that I can see.

Degradation is problematic:

Yes it is.

Identifying intact sperm heads would not indicate if the sperm was from one donor or two. If two male profiles are found we cannot be certain that both profiles came from DNA in sperm heads or other cell types.

But it would indicate that at least one of the samples was from semen, and furthermore that the identity of the semen would most likely be the rapist.

We don't even know if either male profile was derived from sperm head DNA but the judgment presumed it was. That presumption was the basis of the assumption that contamination was possible but only a remote possibility.

I read the judgment differently. I read it as saying that contamination was considered as likely because of the sensitivity of LCN, but from the results obtained they concluded that it was a remote possibility.

I did accept that the judgment says that Dr Evison seemed to accept that contamination would have to be semen. The judgment quite clearly does say that. I'm saying that's a subjective statement not a statement of fact, as implied by usage of the word seemed.

Regards
James

But it is a statement of fact - Dr Evison seemed to accept it. I view the "seemed to" as a qualifier in that he would not definitively declare himself either way, but that he could not offer any other plausible explanation so was left with no option but to agree with the other scientists.

[JamesDean]

Yes I accept that DNA degrades over time, with lots of different factors. In the castree case the sperm heads were collected on sticky tape that had been passed over the victim's clothing. But your last sentence I strongly disagree with, for example, 1. the DNA in both cases is believed to be semen, 2. taken from the victim's clothing, 3. as you say both samples are rather old, 4. most of the evidence was destroyed leaving only a small sample to work from. In fact there are very few dissimilarities that I can see.

There are no similarities in the way that the DNA evidence was collected or stored. The Castree evidence was stored on sticky tape. How is that similar to the A6 murder where the fragment was stored intact? As a matter of fact sticky tape probably helped preserve the Castree sperm evidence as degradation causes sperm to break up. The sticky tape probably helped to stop that from happening whereas dry sperm on a fragment of material is brittle and easily breaks apart, becoming useless for analysis.

But it would indicate that at least one of the samples was from semen, and furthermore that the identity of the semen would most likely be the rapist.

It would indicate that there are sperm heads present in the sample but it would not prove that any profile obtained was from those sperm heads. The presence of sperm heads does not indicate that the DNA contained therein is able to yield a profile after the passge of so much time due to degradation. Even if we do accept that a profile can be obtained from the sperm heads, how can you say that it most likely is from the rapist? It could just as easily be from MG.

I read the judgment differently. I read it as saying that contamination was considered as likely because of the sensitivity of LCN, but from the results obtained they concluded that it was a remote possibility.

The remote possibility is drawn out of the notion that the contaminant has to be semen and the difficulty of imagining a reasonable mechanism by which the contamination could occur.

But it is a statement of fact - Dr Evison seemed to accept it. I view the "seemed to" as a qualifier in that he would not definitively declare himself either way, but that he could not offer any other plausible explanation so was left with no option but to agree with the other scientists.

If he accepted it the judgment would have said so, not say that he seems to accept it. I quote once again:

121. That said we should also record that not one of the respondent’s witnesses
excluded the possibility of contamination. They have expressed themselves in
different ways but the general tenor of the evidence has been that they each
considered the possibility to be remote. That, of course, has to be contrasted
with the opinion of Dr Evison who never moved from his original position as
stated in this judgment.

Note that Dr Evison never moved from his original position.

Regards
James

[Victor]

There are no similarities in the way that the DNA evidence was collected or stored. The Castree evidence was stored on sticky tape. How is that similar to the A6 murder where the fragment was stored intact? As a matter of fact sticky tape probably helped preserve the Castree sperm evidence as degradation causes sperm to break up. The sticky tape probably helped to stop that from happening whereas dry sperm on a fragment of material is brittle and easily breaks apart, becoming useless for analysis.

No similarities apart from that it was a rapists semen taken from the victims clothing. And is there any evidence to support your "matter of fact"?
Edit: Just noticed the "probably" so sorry for the harsh way this qustion comes across.

It would indicate that there are sperm heads present in the sample but it would not prove that any profile obtained was from those sperm heads. The presence of sperm heads does not indicate that the DNA contained therein is able to yield a profile after the passge of so much time due to degradation. Even if we do accept that a profile can be obtained from the sperm heads, how can you say that it most likely is from the rapist? It could just as easily be from MG.

There are two incompatable arguments going on here:-
1. LCN is so sensitive that it gives DNA profiles from the slightest smidgen of contamination.
2. LCN can miss detecting a patch of (visible?) sperm heads.
Both positions can't be right, and arguing for one is arguing against the other and vice versa.

And you must acknowledge that if they confirmed the presence of sperm heads then the possibility of at least one of the male DNA profiles coming from semen is astronomically high.

It's quite easy to say that sperm heads are more likely to be the rapist than MG because of the order in which they had sex with VS - the latest being much more likely to persist than the earliest. Of course natural variances in the quantity of semen in each ejaculate could reverse this general rule but that would be an extreme case.

The remote possibility is drawn out of the notion that the contaminant has to be semen and the difficulty of imagining a reasonable mechanism by which the contamination could occur.

Contamination isn't a magical process. There must be a route or mechanism of contamination. Yes sometimes the route can be complex, but there's always a logical mechanism. If you can eliminate every possible route of contamination then you can rule it out.

What about the paragraph that describes the lack of liquid damage to the samples when discovered? This argument has nothing to do with semen but everything to do with the mechanism of contamination.

If he accepted it the judgment would have said so, not say that he seems to accept it. I quote once again:

Note that Dr Evison never moved from his original position.

Regards
James

If you are arguing about what the judgment specifically doesn't say how about "Dr Evison rules out the suggestion that any contamination would have to be semen"?

In fact, he is the only person who doesn't categorically say the contamination has to be semen - but he does "seem to" accept it. In other words he can not logically and plausibly argue against it, but he dogmatically refuses to formally agree.

KR,
Vic

[reg1965]

Dr Evison when cross examined was possibly asked whether he wholeheartedly disputed the fact that the contamination must have been via semen as was put by the respondents. He could have said that if that is what the forensic results had found he would possibly concur but then went on to say that he believes any other form of contamination was a distinct possibilty given the life cycle of the evidence and the sensitivity of the test involved.
Remember he was outgunned by about to 5 to 1 with regard to expert scientific witnesses.
Reg

[reg1965]

Hi all

The car, when found had no forensic evidence that pointed to a third party bar VS and MG.

Lets accept that VS and MG had sex in the car prior to being waylaid.

When VS was raped where did the rapists semen go? It seems highly unlikely that some would not have remained in the car. None was found on any of VS clothing bar her knickers and a slip.

A nurse on seeing VS when she was admitted to Bedford General stated that her knickers were not on correctly.

If she did not pull her knickers up completely then even if the rapist did ejaculate inside of her then his semen would not have made such an impression on her kincker crotch area (and 5 inches up the back).

A piece of the crotch area was stored away and later found in 1991.

The rest of VS's knickers were destroyed in 1962.

Reg