D): Gas Chromatography (GC) Tests
1: Analyst Ballard testified that the transfer of responsibility for analysing the seized substance was in order to speed the process along and yet he received the methcathinone standard on 05/08/1999 and did not use it until 24/08/1999. Curiously, having received the curator’s standard, this analyst chose to run a Gas Chromatography test (GC) to determine purity only - he said he had already satisfied himself as to the identity of the unknown samples. This analyst said that he does not consider retention time when calculating purity, however having noticed a discrepancy of more than the tolerance level of .2, he did not deem it necessary to confirm his earlier conclusion as to identity especially with regard to his now having the curator’s standard available.
The following is a brief excerpt from the transcript:
Q: In any test of GC between two samples where it was run under identical conditions if you had a retention time of .2 of a minute or over, that is 12 seconds or over, that is significant, isn’t it as a qualitative test?
A: Yes, if I was performing it as a qualitative test and I did obtain that difference then I would consider it, as you say, a signature difference in the fact that I would have if I was relying on that for identification, which I wasn’t, but if I was I would consider re-doing the test.
His Honour: What you might tell me Mr Ballard if you can, my question might be based on a complete misconception; how does the subjective purpose for which the analyst requires a test alter the results of a test? How can it make any difference if you have a significant difference for quantitative/qualitative purposes, wouldn’t that also be a significant difference generally?
A: The results as produced by the instrument wouldn’t vary whether it was for quantitative or qualitative purposes. What I am trying to say is if I was using the GC to identify the substance and I noticed that there was that difference in retention time I would consider repeating it for identification purposes.
Q: But wouldn’t this, having noticed it, wouldn’t it cause you to go back and reconsider your previous view as to the identity of the substance?
A: I considered that the difference in retention times was due to my preparation of the sample as opposed to how the standard was presented, and taking that into account I realised that may cause a difference in retention times and it is not a difference that I call a vast difference, I still call it a small difference in retention times.
Analyst Ballard agreed that if conditions and the instrument are the same and the retention times are different then they are not the same substance. He attempted to explain retention time differences observed by -
a) claiming they were due to the use of different solvents, methanol and chloroform for the curator’s standard and the unknown samples respectively.
b) inferring that differences might be due to the fact that the standard was in the hydrchloride salt form and the unknown samples in the free base form.
c) preparation of the samples after rain.
There was no evidence produced in support of these theories.
The defense analyst said as well as a difference in retention time there was also a difference in peak shape - “The dead give away is that the areas of those peaks are virtually the same and yet one is twice the height and about a third the width of the other.”
Analyst Kibby stated that samples 991685 to 991691 and the methcathinone standard are different compounds.
Concerning the difference in peak shape between standard and samples, analyst Ballard made the following statement:
“If I didn’t know any better from the previous results, I’d say they looked different, I mean they do look different.”
Regarding analyst Ballard’s argument that different retention times were as a result of sample preparation Dr Kibby said that if for example a solvent from chloroform to methanol would produce a marginal difference of 0.4 minutes or 2.4 seconds, as we saw in ex LLL, test results of 27/28 April 2001 for methamphetamine, it would be expected that methcathinone would behave similarly. However, pseudoephedrine, also shown in exhibit LLL, is totally different because it’s an amino in alcohol. It’s injected into a hot injectable set at 250 degrees and will undergo thermal degradation.
In refuting analyst Ballard’s explanation of differences between free base versus hydrochloric salt and the effect of the 250 degree celsius temperature, analyst Kibby says when amine salts are injected into a hot injection port the hydrochloric acid part is only weakly bound to the amine.
Dr Kibby explained:
“In a hot injection port the components are rapidly separated so what actually passes through and is swept by the carrier gas on to the head of the column is the free base. The 250 degree temp makes no difference to the differentiating between the free base and the hydrochloric salt running through the GC. Effectively once injected into the machine as set up in ex U, the results produced should be the same if the substances are the same as clearly seen in ex LLL for the one substance that survives the two tests, namely methamphetamine.”
(Day 75 / P 4104-4110)
The Interaction
Further to these tests, the following is detail of what became known as the ‘interaction’. In setting up the GC machine, the operator sets the parameter of the window at 0.2 minutes, which means that any substance that falls within plus or minus 0.2 of the retention time of the standard, in this case 9.78, is accepted as a match. He then enters the word ‘methcathinone’ into the computer for that window.
Each sample, including the standard, takes 29 minutes to pass through the machine and the tests are run sequentially - analyst Ballard ran the curator’s standard through the machine twice in order to confirm that the machine was operating correctly. The machine recorded the same retention time and the graph showed almost identical peaks next to which was printed the word ‘methcathinone’.
Having run the curator’s standard twice there is then a 94 minute gap - remembering that the samples are run in a sequence at 29 minute intervals - there are no printouts of what was run at this time. Then there is another run of the curator’s standard and just one minute later, not twenty nine, the first of the seized samples was recorded with a retention time of 9.55, a difference of 0.23 minutes which equates to 14 seconds.
The following was given in evidence:
Q: Put it this way, if the window was left at 0.2, we wouldn’t have ‘methcathinone’ on that long peak printed out, would we?
A: It wouldn’t have been printed there by the computer, but since I already identified the substance…
The following day
Q: And as I understand your evidence-in-chief, you would have picked up the results after the last run which was sometime after 6.36pm, is that right?
A: Further looking at this last night, going through them with the times, it appears that I did use the instrument some time after 12.42 and before 14.16 - 2.16 that day.
His Honour: I’m sorry, when you say you used the instrument, you mean for something else?
A: Not for something else, but I believe I had some interaction with the instrument.
Q: If you interacted with the machine there has to be a reason for that, doesn’t there?
A: Yes.
Q: What was your reason?
A: I can’t remember specifically, but I am guessing it’s to, well I am assuming I had seen that the computer wasn’t selecting the peak from exhibit Z onwards as ‘methcathinone’ in those samples, and confirmed it by the previous tests. I believe I changed the window, opened the window a little to include it.
His actions caused the Trial Judge to comment:
"...in many cases the objective test ion activities and retention times, for instance, simply don’t support the conclusions of Mr Ballard. Interaction with the machine GCMS test, as a result of which exhibit GGG was produced, I found inexplicable in terms of objective results being obtained, or at least, if not inexplicable, at least unexplained. One can’t conceive of how it would be a forensic analyst bent on a result which was without any bias, I use the word in a neutral sense, on his part, would interact with the machine."
and a little later in the absence of the jury and analyst Ballard:
His Honour: The Crown should consider its position. If material like this is being presented to the jury, then perhaps the Crown should consider its position when these sorts of things appear. I had an inkling that something like that might be behind it, although I must confess I didn’t fully understand it until I went through the times with you a moment ago. Madam Crown, if these documents have been manipulated in that way, isn’t that something that the Crown should be considering?
Crown Prosecutor: We don’t know that, your Honour. We don’t know the documents have been manipulated in any way.
His Honour: It is obvious, I would have thought, from the evidence that’s been given. If some time before noon the machine has been set at a 29 minute gap and there are two results coming out, one minute after the other, and both of them have got prominently against the major peak the word ‘methcathinone’, doesn’t that rather put some cloud on this material?
Crown Prosecutor: Yes, if that’s the case, but we don’t know--
His Honour: Prima facie, that appears to be the case.
and Justice Barr to observe:
"...what Mr. Ballard described as his "interaction" with the testing apparatus, his putting forward a misleading summary of tests programmed as though they were carried out in terms and his not producing an accurate summary of tests actually done as throwing serious doubt on the integrity of his opinion..."
and Master Harrison to note:
“The issue is whether in the case before me, it is arguable that immunity should not be extended to Ballard in circumstances where he “interacted” with the CMA testing and put forward a misleading and inaccurate summary of tests done. The shortcomings in carrying out the testing of the drug caused serious doubt upon the integrity of his opinion. If the English law were applicable I would allow this matter to go to trial as it is arguable that Mr Ballard’s evidence borders on being classified as fabricated.”
It is worth noting that prior to the ‘interaction’ the two standard runs returned the same retention time of 9.78. Following the 94 minute gap for which there is no documentation, a further run of the standard was performed, again producing a retention time of 9.78.The sample 991685 was run giving a retention time of 9.55 and this was reproduced in all samples through to 991691. A blank was then run followed by the standard which again recorded a retention time of 9.78. This shows that the machine was operating properly and therefore the difference of 0.23 minutes in retention time was real. As well, the four runs of the curator’s standard produced peak widths of 16.6, 16.8, 17.0 and 16.6 respectively compared to the seven sample peak widths of 6.2 for each.
The following is an excerpt from evidence given by Dr Kibby:
Q: Your final expert opinion on the tests run by Mr Ballard on GC for qualitative purposes in relation to the methcathinone standard is?
A: There is one thing that I would like to add: The qualitative tests show the compounds are different and therefore, Mr Ballard’s quantitative estimations on those exhibits Z through to GG are invalid.
Q: Why is that please?
A: You cannot use the response factor for one peak in qualifying the amount of substance on another peak. So not only are the qualitative - Mr Ballard’s qualitative conclusions invalid, his quantitative results are also invalid.
(DAYS 53 - 55, PAGES 2912 - 3021) (Day 75, Page 4081)
Analyst Murtagh was asked to comment on analyst Ballard’s GC tests of 24 August 1999 specifically concerning the difference in retention time between samples and standard, that difference being greater than .2 and actually .23 minutes. This analyst said that he would have looked for other evidence but conceded that if this was the only evidence he would be reluctant to say that the samples were a match for methcathinone. He further agreed that something was wrong, indicated by this level of difference in retention times. He could offer no explanation for the 1 minute gap between runs at 2.16pm and 2.17pm. Analyst Murtagh also expressed no recollection of discussing these test results with analyst Ballard, initially claiming he was unaware of the analysis of samples 991685 to 991691 after he had handed the bulk substance and samples to analyst Ballard. However when shown exhibit HH, his own detailed hand written notes on the printout, he said that those undated notes related to a GCMS test on all seven samples not the GC test of 24 August 1999. The only such test on all seven samples, namely 991685 to 991691, conducted by analyst Ballard was dated 18 January 2001. Analyst Murtagh had left the employ of AGAL in November 1999.
The trial judge in his summing up to the jury gave the following warning:
“I warn you that on this ground alone his evidence may be unreliable. You should therefore exercise the greatest caution in determining whether to accept his evidence and the weight to be given to it. Indeed, if you come to a conclusion that he may deliberately have interfered with these test results in order to obscure a piece of information which was inconsistent with his previously arrived at conclusions as to the identity of these substances, you should, in my view, reject his evidence out of hand and decline to act on it.”
2: On 17/08/2000 a second GC test was carried out on samples 991685 and 991690 some twelve months after the initial GC test mentioned above. The methcathinone standard was also run. Analyst Ballard said this test was done simply as a re-quantitation test and that there was little difference from the earlier GC testing mentioned above. There was a difference in peak shape from the GC testing of 24 August 1999 which he put down to a matter of scaling as these fatter peaks appeared in both the standard and the samples. The defense analyst said that the gas chromatography column is overloaded and the concern is that the difference in retention time in analyst Ballard’s earlier tests of 24/08/99 has been obliterated by the overloading. The peak shape is dreadful, it should be needle sharp as in sample 991690 which shows the peak at 16.684 minutes, needle sharp peaks - if there were compounds eluting in close proximity, you can differentiate between them. These peaks generated for methcathinone, you can’t tell if there are 2 peaks there separated by 13.8 seconds. Overloading eliminates results. Tests cannot be relied upon either for quantitative or qualitative purposes.
(Day 75 / P. 4118)
