The Court of Appeal in Turnbull  QB 224
In response to widespread concern over the problems posed by cases of mistaken identification, the Court of Appeal in Turnbull  QB 224 laid down important guidelines for judges in trials that involve disputed identification evidence.
If the situation arises where the case against an accused depends wholly or substantially on the correctness of one or more identifications of the accused which the defence alleges to be mistaken, it is imperative for the judge should warn the jury of the special need for caution before convicting the accused in reliance on the correctness of the identification(s). Additionally the judge should instruct them as to the reason for the need for such a warning and should make some reference to the possibility that a mistaken witness can be a convincing one and that a number of such witnesses can all be mistaken.
Secondly, the judge should direct the jury to examine closely the circumstances in which the identification by each witness can be made. Some of these circumstances may include: For how long was the accused under observation by the witness? At what distance was the witness from the accused? What length of time elapsed between the original observation and the subsequent identification to the police? Etc.
Whether the case is being dealt with summarily or on indictment and the prosecution have reason to believe that there is such a material discrepancy they should supply the accused or his legal advisers with particulars of the description the police were first given. If the accused asks to be given particulars of such descriptions, the prosecution should supply them in every case. The judge should also remind the jury of any specific weaknesses which had appeared in the identification evidence.
It is commonly accepted that recognition is more reliable than identification of a stranger, however even when the witness appears to recognise someone whom he knows, the jury should be reminded that mistakes in recognition of close relatives and friends are sometimes made.
Quality of evidence
If the quality is good and remains good at the close of the accused’s case, the danger of a mistaken identification is lessened; but the poorer the quality, the greater the danger. When, in the judgment of the trial judge, the quality of the identifying evidence is poor, the judge should withdraw the case from the jury and direct an acquittal unless there is other evidence which goes to support the correctness of the identification. The trial judge needs to identify to the jury the evidence which he believes is capable of supporting the evidence of identification.
If there is any evidence or circumstances which the jury might think was supporting when it did not have this quality, the judge should say so.
Scope of the Turnbull Guidelines
A Turnbull direction need not be provided unless the prosecution case depends wholly or substantially on visual identification. The absence of an adequate Turnbull direction, tailored to the facts of the particular case, will usually require a conviction to be quashed as unsafe. Where the principle or sole means of defence is a challenge to the credibility of the identifying witness, there may be exceptional cases in which a full Turnbull warning is unnecessary or may be given more briefly than in a case where the accuracy of identification is challenged.
Paying lip service to the guidelines will not be enough, nor will it suffice to give a general warning without detailed references to any particular circumstances that may have affected the accuracy of the witnesses’ observation. On the other hand, the guidelines do not require the slavish use of a rigid form of words in every case and a judge may properly point out that a mistaken identification does not necessarily prove that the accused is innocent or that the witness is untrustworthy in other respects, especially if his view of the crime was imperfect.
The guidelines may also need to be followed in cases the disputed identification of an alleged accomplice and an inadequate direction in respect of the evidence against one accused may render unsafe the conviction of another, although this will depend on the circumstances of the particular case. The guidelines are not applicable to cases involving the identification of motor vehicles.
Evidence capable of supporting a disputed identification may take any admissible form, including self-incrimination by the accused, similar fact evidence and other evidence of identification. A judge must identify evidence that is capable of providing such support and warn the jury against reliance on anything that might appear supportive without really having that capability.
Where a judge decides that the identification evidence in a given case is of such poor quality that he would not have left the case to the jury in the absence of supporting evidence, there is no obligation on him to warn the jury that they should not convict on the basis of the evidence of identification alone, should they reject the supporting evidence.
The accused’s silence
An accused’s failure to testify must not be viewed as capable of supporting the evidence against him. The failure of the accused:
To mention facts when questioned or charged which are later relied upon in his defence;
To account for objects in his possession or substances or marks on his body or clothing;
To account for his presence at a particular place; or
To testify at his trial,
may each, in appropriate cases, entitle the court or jury to ‘draw such inferences as appear proper.’ They do not, in themselves, constitute evidence of guilt and should not be seen as a substitute for satisfactory identification evidence, but the absence of testimony or explanation from the accused may legitimately enable a court or jury to infer, in appropriate cases, that the prosecution evidence is correct and that the accused has no answer to it.