Lancashire Constabulary's forensic scientist. Stuart Crosby changed key forensic evidence at re-trial causing the judge to misdirect jury
The witness STUART ARTHUR CROSBY sworn
JUSTICE HOLROYDE: Thank you.
Examination-in-chief commenced by Mr. Nuttall
Q. Is your full name Stuart Arthur Crosby? A. It is.
Q. And will you tell the court please, erm, what your occupation is? A. I’m a forensic scientist. Erm, I have a Bachelor of Science and a Doctor of Philosophy degree in Chemistry. I was employed by the Home Office Forensic Science Service for twenty-eight years, and I’m now employed by Lancashire Constabulary as a forensic scientist.
Cross - examination of forensic scientist Stuart Crosby (Trial 1)
Cross-examination commenced by Mr. Humphries
Q. It’s something of a leap, isn't it, to say that if you find six-millimetre ball bearings years after a device has been set off, that, erm, they’re from the same stock of ball bearings?
A. I understood that the ball bearings that had come from Marland Avenue had been recovered in 1999 and the ball bearings I was looking at the in photograph were also recovered in the 1999.
Q. The, erm, if they weren't recovered the same year, would that affect your conclusion?
A. Yes, it probably would I would be even less certain of the findings.
Q. You say you “would be even less certain.” Do we take it from that that you are less than certain at the moment, but you would be even more uncertain if it was a different year?
A. As I’ve said in my conclusion, erm, the findings provide limited support for the view that the ball bearings are the same. Erm, I think if there had been a number of years separating the two seizures, I may have actually gone down as far as saying that I couldn't comment on the significance of the findings.
Q. Did you in fact have a diameter for the ball bearings from the IED?
A. Erm, only an approximate one as far as I recall from Mr. Ritchie’s statement. I think he measured it at approximately six millimetres.
Q. But there was no scale on the photograph that you saw was there?
A. Yes there was on the ones that I saw.
Q. Was it the scale that appears on photograph 10, which is just a centimetre scale, or was it better
A. No, I think it was better than that. As I said, the photographs I examined had the individual components, erm, on them and consequently they were photographed with a more accurate scale with millimetres on it.
Q. But not like on page 11 which is individual components with again just the centimetre scale?
A. No, I don't think so.
Q. But a minute difference in diameter wouldn't necessarily be apparent, would it, from---
A. Certainly not from the photographs that’s why I’ve, I’ve referred to them as “approximately six millimetres.” I think this is why the weight is more critical in this particular instance.
Q. And could ball bearings they don't have to be made of the same metal, do they?
A. Generally speaking, I think they are steel. Otherwise they, erm, they will be, erm, they will not act as ball bearing.
Q. Has there been any test of the original ones to see if they are steel?
A. Not to my knowledge, no.
Q. Or the ones that you examined?
A. No, for the same reason I couldn't carry out comparisons with the suspected, erm, material from the, erm, explosive device.
Q. If they were made from different materials, they could have different densities, could they?
Q. And therefore ball bearings of the same weight would have different diameters?
Q. And ball bearings of the same diameters would have different weights?
Q. By “limited support” do you in effect mean that you cannot rule out that they are the same?
A. Yes, that is, that is one way of putting it. But, erm, in trying to address our findings to the court, we tend to use a verbal scale, erm, of which starts with: ‘inconclusive or I cannot assist the court whether these ball bearings match or not’ right up to ‘conclusive’ which is what I was with the split-shot because I could conclusively say they were different. And there are steps which start with ‘limited’ which is the first step, ‘moderate support’, ‘moderately strong support’, ‘strong support’, ‘very strong support’. And it’s an, an exponential step each one is ten-fold more than the next. So if you have ‘inconclusive’ as 1., then ‘limited is somewhere between a figure of 1 and 10, ‘moderate’ is between 10 and 100 that findings are more likely given my proposition that they are the same.
Q. And what is ‘conclusive’ on that protocol?
A. Infinite in effect.
A. Infinite in effect. There is no other possibility.
Q. No, but I mean, I’m sorry, if you were talking about the scale and it goes up ten-fold each time.
A. It’s, erm, it should still be infinite. But scientifically speaking, erm, if we’re talking about DNA comparison where a lot of this statistics has been done, they do not tend, sorry, they do not have a ‘conclusive’ at the end of their scale, whereas in (inaudible) comparison group---
Q. Well what’s one down for ‘conclusive’?
Q. Which is what is one down?
A. ‘Extremely strong.’
Q. Right. An ‘extremely strong’ support is what on the scale? A. On the scale? Erm, I don't have them off in my head. Limited, moderate, moderately strong, strong, very strong... basically it’s more than 100,000, possibly even a million.
Q. And we are between 1 and 10?
Q. Well, beyond saying they’re both round, they look similar and they look to be a similar size, is it really any more to it than that?
A. And the compatibly unusual nature of finding ball bearings in those locations.
Q. When pedal cyclists maintain their own bicycles, do you expect anyone who does that to have ball bearings? A. Erm, I don't own a bicycle myself, but they will have bearings on them on the wheels I imagine so, yes, they could well have them.
Q. And if you’re doing your own maintenance or if you maintain or someone in the family maintains bicycles for the post office, it would be a common thing to have would it not?
A. Possibly, yes.
Q. And had you known that the ball bearings that were found came from a post office employee’s house, would that have made a difference as to whether you thought they were a common item and therefore a difference as to whether you could say it was ‘limited support’?
A. No, I would still say that, erm, the occupation of the householder would not affect that conclusion particularly. I would not have the knowledge to know whether post office workers are more likely to have ball bearings in their house than anybody else.
Q. So you’d ignore the fact that it may be a cyclist, or a post office worker---
A. Yes, I’m taking---
Q. ---or a maintenance person?
A. ---I’m taking those as part of the population that may have ball bearings in their house, therefore it’s not unique to have ball bearings in the house, which if it was would be extremely unusual and I would find that the I would consider the findings far more significant. But by saying that I would not expect to find ball bearings in most households is what I’ve used. But if you choose your population to be people who maintain their bikes, then it would be much less, erm, significant.
Q. And had another post office worker’s house been searched around the same time, had six-millimetre ball bearings been found there as well, would it be the same limited support that you’d find that they came from the same stock?
A. Yes, I think it would.
Q. Which in fact would mean that anyone who had ball bearings around that time is limited support for the fact that they’re the same stock.
A. As long as they’re the same size, yes---
A. ---and look in the same condition.
Q. But they looked in different condition when you saw them, didn't they? #
A. (No Answer).
Q. When you saw the photograph...
A. No, some of the ball bearings from Marland Avenue had been cleaned, others were coated in oil. So some were clean some were oily.
Q. And was that the condition they were found in do you know, or was that something that had been done to them before you saw them?
A. I, I can't comment. Erm, those were just the two items as provided to me.
Q. You’re nowhere near sure that they’re the same stock, are you?
Q. No. I’ve no further questions. Thank you.
Cross - examination of forensic scientist Stuart Crosby (Trial 2)
Q. MR NUTTALL: That’s it. Thank you. I think that’s a photograph you’ve seen before is that right Mr Crosby? --
A. Yes this is one of the photographs in a book of the photographs I was, received along with the ball bearings.
Q. Right. So effectively you’ve got JRT1, KAT2, physically you’ve got the ball bearings and we’ve got the photograph here in, as we, our photograph 11 of ball bearings taken from a device fine, found at Mr Winter’s house? --
Q. Now would you tell us please what you were asked to do by the prosecution in relation to all these ball bearings? --
A. In effect I was asked to compare them as best I could. I explained that it would be a difficult comparison given that I understood that the ball bearings shown in the photographs were not available, but I would do whatever I could to compare the ball bearings in the photograph with those I received in the two items. I, also I received a statement from a Mr Richie who had examined the items in the photograph originally and he had detailed some weights and measurements in his statement that I also had access to.
Q. Right. So let’s deal with them bit by bit if we may going back to your report, and I think you looked at JRT1 first is that right? --
Q. Now will you tell us what you found on JRT1? -- A. It was a plastic bag which contained 5 small ball bearings which I measured at approximately 4 millimetres in diameter and 72 larger ball bearings approximately 6 millimetres in diameter. All these ball bearings were covered in what I assume is mill oil, a black coating which appeared to be oily.
Q. So 2 different sizes of ball bearings here is that right? --
Q. 4 millimetre and 6 millimetre and they appear to be covered in some sort of oil? --
A. Yes. At this stage the measurements are only approximate.
Q. Yes. --
Q. We turn to KAT2 then ... --
Q. How many different sizes of ball bearings really are there? --
A. A lot in that there are now metric ball bearings and they tend to go up in ½ millimetre sizes, so if you start at 1 millimetre which is very small obviously, there’ll be 1, 1½, 2, 2½, 3 right up to 10. I’m not sure after 10 whether they just go up in 1 millimetre sizes or even then they might be ½ millimetre sizes, but there would certainly be between 1 and 10 millimetres there’ll be a lot and then in between those there will be imperial ball bearings because so many bearings have old imperial measurements to them and again there might be another 10 or 12 imperial measurements, ¼ inch, ½ inch, 3/8 inch, 7/16 inch, all with a different weight.
Q. So many kinds of ball bearings, some metric, some imperial? --
Q. But as far as the weighing is concerned you find effectively no difference between the weight and the ball bearings we see from photograph 11 used in the device and the ball bearings found at the defendant’s address? --
A. That’s correct.
Q. Yes. Thank you very much, would you just stay there please.
JUDGE GOLDSTONE: Mr Humphries.
This technical report was never used in any of the trials. This clearly states that comparing the bicycle ball bearings from the garage is pure speculation.
The ball bearing sizes used by Stuart Crosby at the re-trial weren't available at the 1st trial or at any point before that.
This detail suddenly became available at re-trial though not disclosed to defence prior to retrial.
The independent report above was never used in trial and like much of the important evidence was never shown to the jury. The professional witness Stuart Crosby clearly has no hesitation in putting his reputation on the line at retrial regarding the ball bearing evidence. It is clear that this new "evidence" is manufactured to suit the prosecution and fit Wilkinsons claims. This could not be challenged as no trial transcript was made available.
The independent report clearly states there are ball bearing in the device had a graphite coating and came from shotgun cartridges, Not from bicycles as Nathan Wilkinson claims. This is just more evidence that was with help from the jury.
This evidence given by Stuart Crosby at the second trial was then used in the judges summing up of the case which resulted in the jury been misdirected
Sergeant Clive O'Beirne was present throughout both trials and was aware that key evidence had changed.