In O v B-M [2019] EWFC B23 Mr Recorder Allen QC noted that a Single Joint Expert had gone beyond their remit in making findings of “fact”.   The parties do not “abdicate” findings to a single joint experts and the expert should not trespass on matters that are for the trial judge.


“…all an expert can do is provide opinion and not evidence.”


The hearing concerned an issue as to whether the parties were lawfully married in Ghana. A single joint expert was instructed to report on the marriage ceremony.

    1. I have read the SJE report of Dr. Osei-Nyame Jnr. dated 19th November 2018 (I believe that he filed a slightly amended report on 22nd November 2018 but there were no material changes) and I listened to his oral evidence with care. He considered the parties’ statements, the DVD and the photographs produced by the parties and their witnesses. He is unequivocal in his view that what he witnessed on the DVD was a customary wedding in two distinct stages – first the ‘Knocking Ceremony’ and second the Engagement Ceremony. His report was (unsurprisingly) accepted by P and challenged by R.
    2. It is clear from the two-page curriculum vitae attached to Dr. Osei-Nyame Jnr’s report that he is highly qualified being a lecturer in African Literature, Languages, and Cultural and Diaspora Studies at the School of Oriental and African Studies. He has prepared numerous expert reports in the past. I am therefore somewhat surprised that his report goes so far as to say at internal page 7 both that a customary marriage “is proven by overwhelming evidence” and that “a customary marriage … is proven to have occurred” and at internal page 36 that “the marriage … can beproven to have taken place” (emphasis added). An SJE gives evidence as to his/her opinion; what this opinion does or does not prove is a matter for the trial judge. I am not entirely sure what Mr. Harley meant when he stated at paragraph 45 of his Position Statement that the parties “have abdicated to [the SJE] to provide independent evidence” but all an expert can do is provide opinion and not evidence.
    3. I accept Dr. Osei-Nyame Jnr’s opinion that what took place in Ghana that day was a two-stage customary marriage ceremony and that this is demonstrated by inter alia the preparation and giving of a dowry and the appointment of “spokespeople” on behalf of both families. I accept that this would not have happened had it been a ‘Knocking Ceremony’ alone. However, if and to the extent that he expresses an opinion that R and his family would have been well aware of the nature of the ceremony that took place – and that as such it is clear that he and they thereby consented to marriage – then I reject that evidence for two reasons. First, I cannot see how he could form such a view as to R’s subjective beliefs. Second, it is contrary to R’s own evidence and that of his supporting witnesses which I accept. Further, although neither the SJE nor I have analysed exactly how much of the ceremony was conducted in languages other than English – languages that I accept R does not speak – it is clear to me that (i) a significant proportion of the ceremony was in languages other than English (i.e. Ga and Twi) – and the SJE accepted in a question from Mr. Thornton that it was “probably fair” that the majority of the ceremony was not in English; and (ii) there is no part of the ceremony where in Englishit is made clear to R that he is about to undergo a marriage ceremony to which he then confirms his understanding and/or gives his consent.
    4. I also accept the submissions made by Mr. Thornton that:
a) Dr. Osei-Nyame Jnr. has viewed the ceremony DVD and read P’s statements through the eyes of (as he put it in his written closing submissions) “a fully informed participant, ofay (sic) with local custom and not a ‘westerner’, domiciled overseas, ignorant of the esoteric nature of customary marriages …”. My conclusion in this regard is fortified by part of Dr. Osei-Nyame Jnr’s evidence, highlighted by Mr. Thornton in his closing submissions, that when asked by Mr. Harley whether a person with just a basic understanding of Ghanaian culture would understand that ‘engagement’ means ‘marriage’ (and with the legal consequences thereof) he replied that they would not without guidance from “more experienced relatives”. Further in answering a question from Mr. Harley, Dr. Osei-Nyame Jnr. said that he “presumed” that both parties knew that this was a marriage ceremony to which they had consented and in answering one from Mr. Thornton said that it would be “improbable” that they would not have understood the significance of the ceremony as they “would have consulted with their families and known what they were doing.” However, there is no evidence (or at least no evidence that I accept) that such guidance was provided to R and I accept R’s evidence that both he and his family were “quitegreen” (paragraph 5 of his Statement dated 16th June 2018) in relation to Ghanaian traditional ways; and
b) notwithstanding that Dr. Osei-Nyame Jnr. said to me that he had watched the DVD “with a very open mind” it is clear from a reading of his report that (as Mr. Thornton submitted) he seems to have accepted the evidence from P’s father and PR-A unequivocally. I therefore agree with Mr. Thornton that it can properly be said that in so doing he “overreached”.