Opinion Evidence.docx

***[Opinion Evidence -- 1 Q's]*** The general rule is that **witnesses may only give evidence of facts they personally perceived and not evidence of their opinion,** i.e. evidence of inferences drawn from such facts. The assumption that it is possible to distinguish fact from inference is arguably...

***[Opinion Evidence -- 1 Q's]*** The general rule is that **witnesses may only give evidence of facts they personally perceived and not evidence of their opinion,** i.e. evidence of inferences drawn from such facts. The assumption that it is possible to distinguish fact from inference is arguably false. - Evidence of tests **showing the speed at which the handwritten notes of disputed interviews had been made, and whether they could have been written in the time claimed by officers, was no more opinion evidence than evidence of the timing of a given journey in order to test an alibi**. The inferences to be drawn from such evidence were for the jury. - A witness was entitled to explain how VAT carousel frauds operate but should not have expressed an opinion on the issue before the jury, namely whether D would have known that they had participated in a fraud. An example of **inadmissible non-expert opinion evidence**. D was convicted of assault by penetration and sexual assault. It was held that the jury had heard inadmissible opinion evidence that V would not have consented to the sexual activity with D. ***[There are two exceptions to the general rule:]*** a. **Non-experts.** A s**tatement of opinion on any matter not calling for expertise, if made by a witness as a way of conveying relevant facts personally perceived by him or her**, is admissible as evidence of what the witness perceived. b. **Experts.** Subject to compliance with CrimPR Part 19 (expert evidence) (see D9.69, D15.75 and F11.46), **a statement of opinion on any relevant matter calling for expertise may be made by a witness qualified to give such an expert opinion**. the evidence may be accompanied, where appropriate, by animations to illustrate the opinion. **Court of Appeal considered the admissibility of graphic 3D reconstructions to reproduce the scene of the crime and to demonstrate a witness's line of sight in support of an expert's opinion that he could not have seen what he claimed.** It was held that whether such reconstruction evidence can assist can only be decided on a case-by-case basis **but will be inadmissible in the absence of sufficiently reliable and precise factual foundations**. In the case before the Court, t**he evidence could only have been of assistance if a large number of variables, relating to such matters as the location of the witness, the accused and objects potentially obstructing the witness's line of sight, had been pinpointed accurately to the exclusion of all other possibilities. This had not been done and the evidence was therefore of no probative value.** If objection to the admissibility of expert opinion evidence is made, it is for the party proffering the evidence to prove its admissibility. Unless the admissibility is challenged, the judge will admit the evidence as sufficient safeguards are provided by the rules on pre-trial disclosure. An objection to the admissibility of expert opinion evidence will necessarily fail if the witness is not an expert and expresses no expert opinion. - where the witness was **not an expert communications data investigator but simply put otherwise relatively complicated telephone data into a more user-friendly format,** using charts, maps and summaries. ***[Non expert opinion evidence -- ]*** A statement of opinion may be given by a witness, on a matter not calling for expertise, as a compendious means of conveying facts perceived by the witness. Thus an identification witness is not required to give a description of the offender or some other person, leaving it to the tribunal of fact to decide whether that description fits the accused or other person identified, but may express an opinion that the accused (or other person) is the person the witness saw on the occasion in question. Likewise, a non-expert may give evidence of opinion to identify an object. Handwriting with which he or she is familiar a voice which he or she recognises or with which he or she is familiar evidence of a person's age or the general appearance of the person's state of health, mind or emotion the speed of a vehicle the state of the weather and the passage of time. The **value of a plate glass window was established by the evidence of a non-expert.** It is submitted, however, that **non-expert opinion evidence should not be received on the value of less commonplace objects or objects such as antiques and works of art, the valuation of which calls for expertise.** On a charge of driving **when unfit through drink, the fitness of the accused to drive is a matter calling for expertise, though a non-expert may give evidence of his or her impression as to whether the accused had taken drink,** provided the **facts on the basis of which that impression was formed are described.** Although scientific evidence is not always required to identify a prohibited drug, police officers' descriptions of a drug must be sufficient to justify the inference that it was the drug alleged. ***[What about the competence of expert witnesses? ]*** Occasionally statute prescribes the qualifications which a person must possess to give expert opinion evidence on a particular matter. For example, a jury shall not acquit on the ground of insanity, except on the evidence of two or more registered medical practitioners, at least one of whom is approved by the Secretary of State as having special experience in the diagnosis or treatment of mental disorder. Those instructing expert witnesses should satisfy themselves as to their expertise and engage an expert of suitable calibre, and the Crown must take all necessary steps to ensure that inappropriate expert witnesses are not called. **a murder trial, it was held that an expert in osteoarticular pathology had the expertise to consider fractures to the ribs as a possible cause of death, but had neither the experience nor expertise to consider other possible causes of death**. Courts need to be scrupulous to ensure that evidence proffered as expert evidence is based upon specialised experience, knowledge or study: **mere self-certification is insufficient.** A person does not become competent as an expert merely because employed by a particular organisation, but will be competent, of course, if the organisation only uses qualified expert. In rare cases it will be necessary to hold a voir dire to decide whether a witness should be allowed to give expert evidence, but in the vast majority of cases the judge will be able to make the decision on the basis of written material. If it appears to a judge that a voir dire may be helpful to decide whether a witness should be allowed to give expert evidence, the judge can canvass that point with the advocates but, if the defence want to contest the competence of an expert in a voir dire, the burden is on them to make such an application to the judge (Francis \[2013\] EWCA Crim 123). If a witness does give expert evidence, the judge has the power, should the need arise, to remove the witness's expert status and limit the evidence to factual matters (G). The expert's competence or skill may stem from formal study or training, experience, or both. A police officer with qualifications and experience in accident investigation was allowed to give evidence, on a charge of causing death by dangerous driving, as to how an accident occurred. A police officer is competent to give expert evidence of the practices, mores and associations of gangs (if admissible as bad character evidence: see F13.49) **if the officer has made a sufficient study, whether by formal training or through practical experience, to acquire a balanced body of specialised knowledge not available to the jury; simple, and not necessarily balanced, anecdotal experience will not suffice.** a doctor was allowed to prove the conversion of figures in an analyst's certificate into the amount of alcohol consumed by D, although not an expert in such conversion, and to prove the rate of bodily destruction of alcohol, having refreshed his memory from a BMA publication. A medical orderly with much experience in the treatment of cuts and lacerations was insufficiently qualified to express an opinion as to whether an inch-long cut to the forehead had been caused by a blunt instrument rather than a head-butt. A doctor who was not a forensic pathologist, but who had spent ten years in emergency medicine and would have dealt with many thousands of cases of lacerations and cuts, had properly been allowed to express an opinion that it was impossible that certain injuries had been caused by a pin and were far more likely to have been caused by a sharp blade. Court of Appeal held that the findings of case workers in the Home Office Competent Authority that a person has been trafficked for the purposes of exploitation are not admissible because such workers, although likely to gain experience in the type of decision-making they routinely take, are not experts in human trafficking or modern slavery. a solicitor, who had for ten years studied handwriting and on several occasions compared handwriting professionally, was allowed to give expert evidence that an advertisement was in D's handwriting. - There is no decision which requires that the evidence of a man who is skilled in comparing handwriting, and who has formed a reliable opinion from past experience, should be excluded because his experience has not been gained in the way of his business. It is, however, really unnecessary to consider this point; for it seems ... in the present case that the witness was not only peritus, but was peritus in the way of his business. ***[What matters call for expertise? ]*** Expert opinion evidence may only be received on a subject calling for expertise, which a lay person, such as a magistrate or a juror, could not be expected to possess to a degree sufficient to understand the evidence given in the case unaided. If the tribunal of fact can form its own opinion without the assistance of an expert, the matter being within its own experience and knowledge, expert opinion evidence is inadmissible because it is unnecessary. Thus a psychologist or other medical expert will not be permitted to give an opinion on the likely deterioration of memory of an ordinary witness. On the other hand, the unlikelihood of the coincidence that a number of complainants all suffered from false memory of sexual assault is a matter calling for expert evidence, being outside the experience of the jury. Although a witness's ability to remember events will ordinarily be well within the experience of jurors, in rare cases in which a witness gives evidence of an event, said to have occurred at an early age, and the evidence is very detailed and contains a number of extraneous facts, an appropriately qualified expert may give evidence that it should be treated with caution and may well be unreliable, because recall of events during 'the period of childhood amnesia', which extends to the age of about seven, will be fragmented, disjointed and idiosyncratic rather than a detailed narrative account. **In the absence of such expert evidence, which is likely to be outside the knowledge and experience of the jury, there is a danger that the jury may find the detailed account more convincing than they safely should, because detail normally enhances credibility to the ear of the listener**. the limits to the evidence that may be given in respect of counselling a complainant in a sexual case. It will only be in the rarest of cases that expert evidence about counselling techniques will be admissible, e.g., where they may have affected the value of the factual evidence of the counsellor. Counsellors may give non-expert evidence as to recent complaint, i.e. evidence of fact that a complaint was made at the time of the events or shortly thereafter (see F6.32), provided that the judge makes plain to the jury that it is not evidence of the truth of the complaint. If there were obvious signs of distress when the complaint was made, evidence of such demeanour may also be given (see also F1.16 and F5.11). **A counsellor may not express any views as to the truth or otherwise of the allegations or the reliability of the complainant**. Nor should a counsellor use over-emotive language. **A counsellor should use objective language and avoid saying anything that can be construed as subjective comment or a statement of personal opinion.** Evidence relating to calls made or received by mobile phones and cell siting, i.e. the location of mobile phone masts through which calls have been routed, will often be drawn from computerised records of the mobile phone service providers as to the date, time and duration of calls and as to the cell sites in question. However, expert evidence will usually be necessary as to whether, and if so to what extent, the fact that a call was routed through a particular cell site is consistent with the phone and its user having been at a particular location. In some cases, it seems that jurors may receive assistance on a matter within their own experience and knowledge **if it is provided by someone who has had more time and better facilities to consider that matter than it would be practicable to afford to them** (see Clare \[1995\] 2 Cr App R 333, where an officer who did not know D but had viewed a video recording about 40 times, examining it in slow motion and rewinding and replaying it as frequently as was necessary, was permitted to give evidence of identification based on a comparison between the video images and contemporary photographs of D). This principle may explain why, although the assessment of age is within the normal experience and knowledge of juries (Land \[1999\] QB 65), expert opinion of age is also admissible. The subjects calling for expertise, which are so diverse as to defy comprehensive classification, include a variety of medical, psychiatric, scientific and technological matters, and questions relating to standards of professional competence. a. accident investigation and driver behaviour b. age, in the absence of documentary or other reliable evidence c. ballistics; blood tests; breath tests and blood/alcohol levels (sometimes including back-calculations thereof, i.e. calculation of the amount of alcohol eliminated in the period between driving and providing a specimen, in order to show that the level was above the prescribed limit at the time of driving d. firearms discharge residue e. forgeries f. handwriting identification (including the analysis of indented impressions of handwriting, left on one document as a result of writing on another, and revealed by Electrostatic Detection Apparatus (ESDA) g. fingerprint identification h. ear-print identification i. voice identification (see F19.25) j. identification by facial mapping k. expert evidence of which may form the basis of a conviction l. facial identification by video superimposition m. 'Reverse projection', the technique of superimposing one CCTV recording upon another as a means of comparing, e.g., the height of the individuals shown n. gangs, their way of operating, language and culture o. Genetic fingerprinting (the technique whereby a human cell taken from a sample of blood, saliva, semen or hair is analysed to reveal a person's DNA or genetic 'fingerprint' p. the physical signs of child sexual abuse q. 'shaken baby syndrome' r. Sudden Infant Death Syndrome (SIDS) s. Insanity t. Automatism u. diminished responsibility v. and the competence of a medical practitioner w. expert opinion evidence as to the state of knowledge and skill of a physician as shown by his treatment of the case in question. ***[What about opinion on ultimate issues? ]*** an expert is allowed to express an opinion on an ultimate issue, **provided that the actual words the expert employs are not noticeably the same as those which will be used when the issue falls to be considered by the court**. I myself would go a little further in that I cannot help feeling that with the advance of science more and more inroads have been made into the old common-law principles. Those who practise in the criminal courts see every day cases of experts being called on the question of diminished responsibility, and although technically the final question 'Do you think he was suffering from diminished responsibility?' is strictly inadmissible, it is allowed time and time again without any objection. a. whether wounds were self-inflicted b. insanity c. diminished responsibility, in cases where the expert has properly expressed a view on all four of the matters set out in the Homicide Act 1957, s. 2, as amended d. the unreliability of a confession e. establishing identity by expert evidence of facial mapping f. a rape case, the effects of alcohol on the ability to give informed consent g. As to possession of drugs with intent to supply, where the Court concluded that the opinion expressed in effect amounted to an assertion that D was guilty as charged) experts should not usurp the role of the fact-finder as the ultimate decision-maker on matters that are central to the outcome of the case. Thus a psychologist may give evidence of opinion as to why the accused might be disposed to make an unreliable confession but is not entitled to assert that the confession made is in fact unreliable - a case in which a consultant surgeon was charged with manslaughter by gross negligence and experts had given evidence that **D had been 'grossly negligent' and had also used other descriptions such as 'very bad practice' and 'recklessness'. It was held that although the jury had been told that they were not bound by the views of the experts on the ultimate issue, the experts had failed to give explanations for the terminology of many of their opinions and therefore there was a danger that the jury may have merely accepted their conclusions.** ***[What is the duty of the experts? ]*** An expert must help the court to achieve the overriding objective by giving objective, unbiased opinion on matters within his or her area or areas of expertise and by actively assisting the court in fulfilling its duty of case management under r. 3.2, in particular by complying with court directions and at once informing the court of any significant failure to take any step required by such a direction. This duty overrides any obligation to the person instructing the expert or by whom the expert is paid; and this duty includes an obligation a. to define his or her area or areas of expertise in the report and when giving evidence b. when giving evidence, to draw the court's attention to any question to which the answer would be outside the expert's area or areas of expertise, and c. to inform all parties and the court if his or her opinion changes from that contained in a report served as evidence or given in a statement. ***[What is the function and weight of expert evidence? ]*** The duty of the expert witness is 'to furnish the judge or jury with the necessary scientific criteria for testing the accuracy of their conclusions, so as to enable the judge or jury to form an independent judgement by the application of those criteria to the facts proved in evidence'. - It is a misdirection, therefore, to tell the jury that expert evidence should be accepted if uncontradicted. Court of Appeal refused to interfere with a conviction despite medical evidence of insanity. Equally, it is **incumbent on magistrates to approach the evidence of an expert critically**, **even if no expert is called on the other side, and to be willing to reject the evidence if it leaves questions unanswered.** When expert evidence is given on an ultimate issue, it should be made clear to the jury that they are not bound by the opinion, and that the issue is for them to decide**, but there is no requirement that such a warning be conveyed in any particular way.** 'Where there is simply no rational or proper basis for departing from uncontradicted and unchallenged expert evidence then juries may not do so.' The Court of Appeal approved (at \[45\]) the standard direction in the Crown Court Bench Book, which suggested (after the usual directions and appropriate stress on the need for a jury to consider all the evidence) a **direction of the following kind: 'Where, as here, there is no dispute about findings made by an expert you would no doubt wish to give effect to them, although you are not bound to do so if you see good reason to reject them.'** The Court held that such an approach acknowledges that, if unchallenged expert evidence on a particular point calling for such expertise is to be rejected by a jury, it must be rejected for a reason. It is wrong to direct a jury that they may disregard scientific evidence when the only such evidence adduced on a particular question dictates one answer and only a scientist is qualified to answer that question. where the **medical evidence of diminished responsibility is uncontradicted and the jury return a verdict of guilty of murder, if there are facts entitling the jury to reject or differ from the expert opinion, the Court of Appeal will not interfere with the verdict; but if there are no facts or circumstances to displace or throw a doubt on the unchallenged medical evidence, such a verdict would not be a true verdict in accordance with the evidence**. a conviction for murder was upheld despite uncontradicted medical evidence of diminished responsibility. Matheson and Bailey were distinguished on the basis of the greater weight and quality of the medical evidence in those cases. **Two clear principles emerged from the cases, on the issue of diminished responsibility**: a. if there were no other circumstances to consider, unequivocal, uncontradicted medical evidence favourable to an accused should be accepted by a jury and they should be so directed; and b. where there were other circumstances to consider, the medical evidence, though it be unequivocal and uncontradicted, must be assessed in the light of the other circumstances.