by Cliff Todd
And so we did something that, to my knowledge, had never been done in the history of FEL – we started a two-shift working pattern, from 7 am–11 pm I think. This may not seem like a very big deal to some people, but the civil service very rarely works this way, and FEL is a civil service lab. It is a full forensic lab, there are always at least two people on-call 24/7, and it can and occasionally does, work at any time of the day or night or weekends. But this is just if necessary to deal with a particular incident, and FEL had never previously had anything approaching this scale to deal with.
If you are wondering about exactly how much history FEL has, well, its first incarnation was in the 1880s – it still has some of the bound ledgers from around that time! This was in response to a series of so called ‘Fenian Outrages’ – wouldn’t you know it, basically Irish terrorism! Cycles of history, huh? OK, at the time, it was only an investigator (Colonel Majendie) and a chemist (Dr Dupree), and probably an assistant or two, but that was the start of the FEL, and it has continued in one form or another up to the present day. So it has some pedigree.
I can’t remember how long this went on for, a few weeks I think, but it was certainly a landmark for the FEL, and I put this in here, just to try and convey the sense of continuing pressure at the lab, not just in the first three to four weeks, but in the months following on from that.
December – New Year 2006
I am going to digress briefly here – a bit more personal stuff, not really about the 7/7 and 21/7 story, except how it relates to me as a personal recollection. So if you just want the story bit, skip to the next heading, and you won’t miss anything. This is really just for my benefit. Call it another, rather long-winded, musing on the possible merits of some sort of counselling after such kinds of incidents.
Back in 2004, Vanessa and I had started to think a little bit about what we might do when I retired. I said I had occasionally wondered about having a boat – something with a cabin and an engine; hadn’t thought further than that. Well, she was really enthusiastic about the idea, so we thought – let’s buy a boat now, I could do some courses, we could use it in the summertime, and get used to it, so that when I did retire we’d both be ready to do some real trips, maybe around the British coast, over to France, really spend some time with it, and each other. So we did buy a boat, 30 foot, proper big cabin, cooking facilities, comfortable double bed in the main cabin, and two small extra berths in a small aft cabin, nice aft deck. We bought it in Southampton and sailed it round to Brighton, where it was to be berthed. I think this was early August. Then within two or three weeks – Vanessa was diagnosed with breast cancer. Well, that basically wiped out the rest of the summer, with all her tests and then treatment, taking us right into 2005, without hardly using the boat at all. Now by about June 2005, her treatment was mostly over, certainly the intensive stuff, so we both thought – OK, this summer we’ll really get back into the boating thing. And then 7/7 happened. So, as must be apparent from all the foregoing, I was effectively gone for the whole of the summer again, and the boat just sat there for another year.
So when it came to December again, I suppose I sort of took stock. I don’t know how many hours of overtime I had worked by then, but many hundreds. Normally I wouldn’t get paid for overtime, at that level some is informally expected, and anything more than a few hours is then supposed to be taken as time off at a convenient time. Well, that clearly couldn’t happen – I’d be off for months! An exception was made for this particular situation, and I was given a payment for some of the overtime – which meant that I had some unexpected extra cash. So I suggested to Vanessa that we go away somewhere for Christmas and New Year – and we would fly business class! – something she’d never done, and was really excited about. We settled on the Florida Keys. And we did have a wonderful holiday.
But what’s the point of all this? As I recall it, I was just thinking, we’ve missed out on a summer holiday, it’s been a difficult time, let the world go hang for a couple of weeks and have a decent break. The subtext being that everything will be fine again after the break. I never had a conscious thought that maybe I had changed a bit, but now I think maybe I had – and maybe that had affected Vanessa too. Or maybe subconsciously I was aware of something. At any rate, after this year, the joy had gone out of the boat, certainly for me, and maybe for Vanessa, or maybe she just saw that in me. I eventually sold it in 2009. This is the same mental territory I wandered into earlier, which I then left alone, and which I thought I could come back to in digressing here. Except that again, suddenly, I get a real sense of treading on thin ice – so maybe it is best to just leave it alone. OK, perhaps there is something to be dug out here, but what purpose would it serve now? I’m functioning OK (I think anyway), and thanks to the cancer Vanessa’s no longer here, so there’s no relationship to rescue or work on. Perhaps it would have helped at the time, but it’s too late to change anything now, so why dwell on it?
In summary, I’m more inclined to think now, than I was then, that some sort of counselling, at the time of a major incident, is probably a good idea. Enough.
Pagan Truffle
What!? Well, quite. Dstl has its own random naming system when it wants to give a name to some particular project – and this is the kind of result you get!
By Christmas, the judicial process for 21/7 was well under way, and I had been advised by prosecution counsel that the main argument by the defence, in the upcoming trial, was likely to be that the devices weren’t intended to explode and harm people, nor could they – they were just intended to scare people. There was no dispute that they had actually made and operated the devices. This being the case, counsel asked me if, and how, we could show that not to be the case, i.e. to prove that the devices, as constructed, could explode.
Well, this would require a significant programme of explosive trials, and since we knew very little about the properties of these types of mixtures, that would be quite a major project. This is not something the FEL could do itself, but there was another Dstl department, also based at the Fort, that did precisely this kind of work. After discussions with them – I will call them Explosives Group (EG) for convenience – I advised counsel that this work could be done, but it would take a minimum of six months, and it would mean the EG suspending their current work programme to do it. And that would need instruction from a very high level, beyond just Dstl, to make it happen. So, at the committal proceedings in December, prosecution counsel made this application to the judge, and after a lot of robust discussion from all concerned, the judge eventually ruled that this work was in the national public interest, and needed more urgently than their current work programme, and thus made a court order that it be done – to be completed for the start of the trial, by early June 2006. This was quite an interesting reminder to me of just how much power senior judges have – not much stands in the way of a court order.
And so project Pagan Truffle was born. From my point of view, this was a good outcome – but there was a downside. This work would ultimately have to be written as a legal statement and presented in court, and cross-examined as the defence saw fit. The EG could do all the work, but they are not forensic scientists, and they were very clear that they would write a scientific report, as normal, but had no intention of presenting this in court – which I actually agreed with. In principle, scientific work should not be presented in criminal trials by non-forensic scientists, unless completely unavoidable – and in a part of this case that did happen, actually on both sides. And although not fully apparent at the time, in both instances where non-forensic scientists did give evidence, it did not go well for them, some consequences of which are still being felt to this day! More of that later. Anyway, to get round this issue for Pagan Truffle, the EG would basically be deemed to be working under my direct supervision, by which means, I would be the one to actually write a legal statement and present it as evidence in court. This is a standard way of working in forensic
labs: court-going forensic scientists (case officers) clearly can’t physically do every test or examination themselves; they use assistants, who generally do not have to give evidence – they are deemed to be directed and supervised by the relevant case officer. But the supervision must be real, which meant I would have to spend a lot of time with the EG, with their planning, and preparation – and most importantly when they did the explosive firings. Fun for some of the time (childish, but who doesn’t like blowing stuff up?), but yet more time away from home, since this couldn’t be done at the Fort – these explosive firings were too big to be carried out there. And more stress for me, I was somewhat out of my comfort zone here, some of these EG scientists really are rocket scientists!
The question was – under what conditions could these mixtures explode, if at all? All we really knew at this point was that they consisted of flour and hydrogen peroxide. We only had a limited time and could only do a limited number of tests, so what to choose? The size of charge chosen was nominally five kilograms, based on the size of the container of the abandoned device. Eventually we came up with a list of twenty-four variations of this five-kilogram charge to test, which was the practical maximum we thought we could do in the time available. First we had to choose what ratios of flour and hydrogen peroxide. From a theoretical chemistry perspective, it is possible to work out, approximately, what the most efficient ratio is likely to be, so we chose that, and then one ratio either side of that, giving us three different ratios. But hydrogen peroxide is available in different strengths, so each of those ratios would be made up with one of two different strengths of hydrogen peroxide. One was a strength that could be easily bought by the general public, the other was the strongest commercially available, which cannot be bought by the general public, only by accredited commercial users. So this now gave six variations. But we also wanted to know if, and how quickly, such mixtures would be likely to deteriorate with time – very likely, given their highly reactive nature. So each of the above mixtures was made and then left for one day and five days before firing, it being felt likely they would be made on one day then used the next (the mixing is not a quick process), or at least not left for longer than five days before being used. Now we have twelve variations. Finally, each of those twelve variations would be fired with two sizes of initiator – a medium size one, and one several times bigger, this (large) size being chosen as the size at which, if the mixtures don’t explode, then they are probably not going to explode under any conditions. Which gave us our twenty-four test firings.
By the end of May the results were in. And they told us that with the weaker hydrogen peroxide, none of the mixtures would explode. However, with the stronger hydrogen peroxide, all the mixtures showed some reaction, with the chemically most efficient flour/hydrogen peroxide ratio mixtures, all detonating fully and reliably under all the other conditions. So flour and hydrogen peroxide mixtures can indeed make effective and reliable explosives – but only within a certain range of mixtures. At the end of our planned tests, we had a spare day, and some spare mixtures left, so we did two more firings. Despite the results we had got, I still felt that the size and make-up of the bombers’ initiators would be an issue – they had used TATP, an improvised explosive, not possible on safety grounds for us to replicate on these tests. So on the last day we made two duplicate devices with the most efficient mixtures, and fired them, each using just a small size initiator – much smaller than the medium size initiator we had been using to test the mixtures up to then. And both detonated. To the eye, these were still full detonations, but on the instrumentation, we could see that in one case, the detonation was not quite a full one – an important observation which suggested that the shock from a small commercial initiator was perhaps right on the edge of what is required to make such mixtures explode. And this was probably as close as we could safely get at that time to the shock the bombers’ own initiators would have actually produced.
The Forensic Evidence – Pre-trial (for 21/7)
Before I get properly into the legal side of this story, I need to be clear on where I am coming from in writing this. This is a personal recollection of a significant episode in my life, written from an absolutely personal perspective. As such, it may be that it gives the impression, at times, that the evidence I, and other staff at the FEL, gave at the trial was the main contributor to the final outcome. Such an impression would be wrong. In any trial, the final outcome is the result of the court’s consideration of all of the evidence presented to it, and in this case in particular, there was a huge amount of evidence given by a large number of people and organisations. No single part of that evidence should be deemed more important than any other, it is the sum total of all the evidence that counts. My evidence was no more or less important than that of the other FEL staff, or anyone else involved in the case. So it is in no sense an objective chronicle of how the trial progressed, nor is it a commentary on how the court came to its conclusions. It is simply my recollection of my own involvement in a significant national event, seen from a distance of over ten years.
Now, while Pagan Truffle had been going on, back in the lab we had not been idle. Amongst the large amount of material that had been examined were various pieces of equipment and other items taken from the premises believed to be the main 21/7 bomb factory in London. The equipment included a number of aluminium pans, that all showed signs of severe corrosion, and amongst the other items were several empty bottles of hydrogen peroxide hair products. The corrosion damage was shown to have been likely caused by exposure to hydrogen peroxide (I think this was determined by the Forensic Science Service Lab in London, not FEL). This only really made sense if they had been used to heat the hydrogen peroxide – which in turn only really made sense if they were being used to make the hydrogen peroxide from the bottles, into a more concentrated form. Precisely what would be required to make an effective explosive with flour.
And this brings us to a key question, which we had not been able to answer explicitly – and neither had any other laboratory. How concentrated was the hydrogen peroxide in the actual mixtures recovered? As noted above, we had to get rid of most of it; all we had left were small samples. And neither we, nor anyone else had a proven method for doing this analysis – unsurprisingly perhaps, since there had never been a need for that before!
Now, it is the nature of forensic science, that all measurements, and tests should only be done using procedures that have been demonstrated, to the satisfaction of the profession, to produce reliable results, i.e. they have been properly validated. Which is a lengthy process. So, while there were ways we could have tried to measure the concentration of hydrogen peroxide in the mixtures, we could not have produced a reliable method in time for court. Or, even more to the point, within the time that the original samples could still realistically be considered close to how they had started out – i.e. before they had ‘gone off’ (in the milk sense).
To try and get round this, I had arranged for another series of Gap tests to be done, using a range of different mixtures and strengths of hydrogen peroxide and flour. Comparing the results of those Gap tests with the single one we had done with the actual material recovered from the scenes, would give us at least an approximation of which of these known mixtures was closest to the actual material. These Gap tests showed that the scene material was closest to a mixture where the strength of the hydrogen peroxide was sufficient for the mixture to reliably explode, but not reliably from a small initiator – it would need at least a medium size to make it reliable.
To my mind, we now had reliable evidence, to a good approximation, of the composition of the scene material and, in particular, to the fact that it could reliably explode under the right circumstances. And just as importantly, the Gap tests are easily understood – they are based on a simple assessment of the metal fragments produced, and a visual estimation of fragment size, which the jury could see for themselves – they were photographed for this purpos
e.
Unfortunately, this very simplicity was a bit of a disappointment to the police – they will always take ‘super science’ over a basic visual test, if it is available. And at the FEL over the past couple of years, we had been researching a new analytical technique called Isotope Ratio Mass Spectrometry (IRMS) – which is indeed ‘super science’. However, we were looking at this for just some very specific types of analysis, and even with those, it was still a research tool, absolutely not for court use at that time. But for some reason, which I didn’t understand then, and still don’t now, the police got the idea that this could be used to tell us the strength of the hydrogen peroxide in the scene material – and in a much more ‘scientific’ way. So they asked me if the FEL could do this analysis for them – which I flatly refused. I explained that we were still learning about the technique, and even then only for specific uses that most certainly did not include what they were asking for. So, when they finally realised it simply wasn’t going to happen at the FEL, they asked me if we could recommend someone who could do it for them. To which I said, “No, we can’t, it’s highly unlikely anyone with a forensic background could or would do this, it’s the wrong technique, you don’t need it, and if you do find someone, there will just be a big argument between experts in court, which no one will understand. All it will do is muddy the water, which is currently not muddy!” If this gives you the impression that I was irritated because they wouldn’t just let it go, you would be correct!
Anyway – they wouldn’t let it go. And failing to find any forensic lab that could or would do it, they found an academic, at a university. Now this person was using IRMS for another, different type of analysis to what we were doing – and also, nothing like what was being asked in this case. And while he was no doubt an expert with the technique in his own field, like everyone else, he would be starting from scratch with the question being posed (i.e. how strong was the hydrogen peroxide in the mixture?). Neither was he a forensic scientist and, in my opinion, he had no idea what he was getting into. I will come back to this later, but basically the seeds were sown here for a potential appeal after the trial had finished.
