[2025] UKUT 215 (AAC)

As I have indicated above, the appellant took his first, second and sixth grounds of appeal together.

The appellant argued under his first ground of appeal that the PATS ought to have treated GWI as an organic disease. Absent a pure perversity challenge, which is not made, that is not an issue of law.

The appellant’s argument under his first ground of appeal involved a quite detailed consideration of the medical literature which was before the PATS and an argument that the PATs had misunderstood this evidence. There are various flaws and problems with this argument, not the least of which might be said to be the basis on which an error of law tribunal judges whether the expert fact-finding tribunal “misunderstood” the evidence.

The key flaw, however, is the failure to locate the PATS’s consideration of this medical literature in the context of its acceptance of Dr Madhok’s evidence. I will return to this once I have addressed the flaws in the arguments the appellant made about the PAT’s approach to the medical literature.

The first flaw in the argument is that the PATS plainly did not misunderstand the Fukuda report. That report, as the PATS stated in paragraph 34 of its decision, was designed to provide case or classification criteria not diagnostic criteria. Moreover, the PATS was also right in noting that the introduction to the Fukuda report stated that, in terms of GWI, no specific disorder had been identified and the etiological basis and clinical significance of the symptoms remain unclear. Nor is it open to any reasonable argument that the PATS failed to take into account that the article was from 1998. Paragraph 34 of the PATS’s decision expressly stated that the report was published in 1998. The PATS were on the face of it aware that this report was from 1998 and it was rationally entitled to take it into account as part of the history of understanding relating to GWI.

The second argument the appellant made about the medical literature concerned how the PATS dealt with the Chen article at paragraph 33 of its decision. The PATS said it had a number of caveats about this report. The most obvious caveat was that the report had a tiny study sample of only 21 patients and as such it was not statistically significant. The PATS considered this could be seen from the underlying hypothesis that such dysfunction was caused by exposure to agents such as carbamates and organophosphates, whereas there was no suggestion of such exposure in the appellant’s case and equally there was no evidence the appellant had mitochondrial DNA damage. The PATS finally noted that the Chen article recognised that:

“GWI is a chronic multi-symptom illness not currently diagnosed by standard medical or laboratory test…”

The appellant took me to the Chen article and argued by reference to the “(p)” in it that this showed that it did contain statistically significant information. This was another instance of the argument seeming perhaps to move into evidential reargument. Moreover, the PATS may have been using ‘statistically significant’ in a way different from the statistical sign of (p). Be all of this as it may, I am satisfied that PATS committed no material error of law in its understanding of the Chen article. The PATS in my judgement was entitled to take the view that the report was not relevant evidence in respect of the appellant because, even outwith its small sample of patients (and the statistical significance (or not) of the same), its underlying hypothesis was that mtDNA damage was caused by exposure to carbamates and organophosphates, and there was no evidence of that the appellant had mtDNA damage. Even if, as the appellant argued, the PATS was wrong about him not having been exposed to carbamates and organophosphates, because his evidence was that taking the NAPS tables was equivalent to taking carbamates and organophosphates, that still leaves the article lacking relevance for the appellant because there was no evidence that he had mtDNA damage.

In addition, these criticisms by the appellant of the PATS’s understanding of the Chen article leaves undisturbed the quotation set out at the end of paragraph 49 above. And the PATS was entitled to take that view expressed in the Chen article into account in deciding whether GWI is an organic disease.

The last piece of the medical literature in respect of which the appellant criticised the PATS’s approach is the Haley article, which the PATS addressed at paragraph 35 of its decision. As set out above, the PATS found this article lacked relevance to the appellant because of:

“the absence of any evidence that he was exposed to nerve agent during his brief time in theatre. Although the appellant did give evidence that he heard chemical alarms, he did not suggest that there was ever any exposure to agents such as organophosphates.”

The main criticism the appellant highlighted before about the PATS here is that it was wrong to consider there was no evidence of low level exposure as there may have been a sufficiently low level of exposure which could not be detected alarms. There is nothing in this point, even if it is not just evidential argument. If no alarm could detect the nerve agent then there simply was no positive evidence that the appellant had been exposed to nerve agents. As I understood it, Mr Haddow accepted this, but he argued that this argument and criticism was relevant for the causation, and the ‘reasonable doubt’ stage of the analysis. This cannot help the appellant either as the PATS having found that GWI is not an organic disease, and that therefore the appellant did not (and could not) have GWI, never got to that stage of the analysis. Putting this another way, the criticism the appellant makes of paragraph 35 in the PATS’s decision does not assist him in his arguments about the PATS’s approach to whether GWI is an organic disease.

These arguments therefore take the appellant no further. However, as I have said above, a crucial omission is the failure to see the PATS’s approach to the medical literature in the context of Dr Madhok’s evidence.

I accept the Secretary of State’s argument that the PATS accepted, and was entitled to accept, Dr Madhok’s evidence of the importance of having accepted diagnostic criteria in terms of identifying whether something is an organic disease. It was also entitled to take from Dr Madhok’s evidence (i) that it was important to distinguish between diagnostic criteria and classification or case criteria, (ii) that there were no accepted diagnostic criteria for GWI, and (ii) that classification criteria cannot be used as diagnostic criteria. It is worth remembering that it was the appellant case to the PATS (see paragraph 40 above) that “GWI is now recognised as a single diagnostic entity”. Dr Madhok’s evidence plainly stood contrary to that case. Moreover, the medical literature did not stand against this evidence of Dr Madhok.

In addition, and focussing on what I have said is the omission in the appellant’s argument about the PATS’s approach to the medical literature, PATS’s approach to that literature has to read in the light of its acceptance of Dr Madhok’s evidence. It is in this sense, in my judgement, that the PATS then found that the overall problem with the medical literature was: that no unifying underlying pathology had been identified (paragraph 36 of the PATS’s decision); it was wrong to treat classification criteria as diagnostic criteria (para. 37); in the absence of diagnostic criteria, it was difficult for the PATS, in the absence of a medical diagnosis, to find the appellant had GWI (para. 37); and GWI was a diagnosis of exclusion and there were co-existing medical conditions which explained the condition (para. 38). Those were findings the PATS was entitled to take on the totality of the evidence before it.

There was an attempt by the appellant to argue in his reply that the PATS ought not to have relied on Dr Madhok’s evidence. As far as I could see, these were either arguments that were made to the PATS or should have been made to it. For example, Mr Haddow told me that the appellant had argued before the PATS that Dr Madhok’s evidence should be excluded in its entirety but the PATS did not accept this. That was a matter for the PATS to decide. Mr Haddow accepted that he had not made a submission to the PATS that Dr Madhok was giving evidence outside his instructions, but he had argued to the PATS that Dr Madhok was not an expert in GWI. This last point takes the appellant nowhere as paragraph 23 of the PATS’s decision shows Dr Madhok accepted that he was not an expert in GWI. In any event, there is no ground of appeal before the Upper Tribunal which argues that the PATS was wrong to allow Dr Madhok to give evidence.

I have dealt to some extent with the appellant’s second ground of appeal (was the status of GWI academic) at paragraphs 41 and 42 above. I should add to those paragraphs that the appellant’s Notice of Appeal to the Upper Tribunal argued, contrary to this case before the PATS, that the PATS was wrong to direct itself as it did in paragraph 39 of its decision. However, in so doing he argued as follows (at paragraph 26 of his Notice of Appeal):

“If GWI is an organic disease and the Appellant demonstrates on the balance of probabilities that he has that condition (which, in the absence of any definitive diagnostic scientific test, will necessarily require consideration of his symptoms), then he need not demonstrate that each individual symptom is caused by his service. The only further necessary step is for the tribunal to consider causation; that is: whether there is a reasonable doubt GWI may be related to his service.”

I make two observations about this. First, and as I have said before, as the PATS found GWI is not an organic disease, and it therefore must follow that whatever medical conditions or symptoms the appellant had he did not have (indeed could not have) GWI, the issue of whether GWI was related to service did not arise. Second, on the appellant’s own argument in the brackets in paragraph 26 of the Notice of Appeal, it is accepted that absent a diagnostic test for GWI, the appellant’s individual symptoms would need to be considered. That was the position the PATS reached, and was entitled to reach for the reasons I have given above, and in proceeding as it did it was also answering the case the appellant had expressly asked it to address. In so doing, and in these circumstance, it did not materially err in law in what it set out in paragraph 39 of its decision.

Another way of looking at paragraph 39, which comes to the same result, is that having accepted Dr Madhok’s evidence, and so accepted that there were no diagnostic criteria for GWI, the PATS had to consider the individual symptoms claimed (e.g., depression and memory loss).

As for the sixth ground of appeal and causation, save for the conditional argument made in paragraph 26 of his Notice of Appeal which does not arise and the point I have addressed in paragraph 53 above, the arguments made by the appellant are about the PATS’s approach to causation in relation to the individual symptoms which it accepted the appellant had. I will therefore deal with causation in that context later.