“[A]n expert’s opinion represents his reasoned conclusion based on certain facts or data, which are either common cause, or established by his own evidence or that of some other competent witness. Except possibly where it is not controverted, an expert’s bald statement of his opinion is not of any real assistance. Proper evaluation of the opinion can only be undertaken if the process of reasoning which led to the conclusion, including the premises from which the reasoning proceeds, are disclosed by the expert.”
“As with judicial or other opinions, what carries weight is the reasoning, not the conclusion.” 49. In Davie the Lord President at p 40 observed that expert witnesses cannot usurp the functions of the jury or judge sitting as a jury. Recently, in Pora v The Queen[2015] UKPC 9 ;[2016] 1 Cr App R 3 , para 24, the Judicial Committee of the Privy Council in an appeal from New Zealand, stated: “It is the duty of an expert witness to provide material on which a court can form its own conclusions on relevant issues. On occasions that may involve the witness expressing an opinion about whether, for instance, an individual suffered from a particular condition or vulnerability. The expert witness should be careful to recognise, however, the need to avoid supplanting the court’s role as the ultimate decision-maker on matters that are central to the outcome of the case.”
“The person speaks a variety of [language or dialect] found- with certainty in (or certainty not in): - most likely in: - likely in: -possibly in:” 90. Sprakab’s account of the measure of these phrases is as follows:“If the analyst is certain that the analysed language is found in a specific region, he/she uses the degree of certainty “with certainty in”
“The size of the Bajuni population in Somalia in the years and decades even before The Troubles is disputed: the figure of ’perhaps 3,000 to 4,000’ (Cassanelli 1995) is the best. Allowing for an annual compound increase of some 2% and the leakage down to Kenya, Cassanelli’s figure fits reasonably well with the 1926 figure.”
“Most anomalous are his [the appellant] answers to the questions about clans. Asked about his father’s clan he replies Isaaq and Arab. Asked about his mother’s clan he replies half-Somali half-Kenyan. He says his own clan is that of his father. Asked about clans on Chula, he says Dir, Isaaq, Darood, Hawiye; Bajuni who grow up in a Bajuni area with two Bajuni parents can state their clan and the clans of their parents but he cannot: he says Isaaq (a Somali clan, Kenyan Arab). Asked to name the clans in Bajuni Chula he reels off the major Somali clans. The nearest equivalent in the UK would be to ask a Highlander in Scotland called Macdonald for the surnames of his parents and he replies Smith, Jones and Robinson and asked for the names of the clans in the neighbourhood and he gave the same answer.”