Evidence that tends to prove the identity of a person. A person's identity may be proved by direct evidence (even though this may involve a witness giving opinion evidence) or by circumstantial evidence. Secondary evidence of an out-of-court identification by a witness (as where the witness has picked the accused out in the course of a video identification or an identification parade) may also be given to confirm the witness's testimony. In criminal cases, the case of R v Turnbull  QB 224 (CA) provides that whenever the case against an accused depends wholly or substantially on the correctness of an identification of the accused that the defence alleges to be mistaken, the judge should warn the jury of the special need for caution before convicting the accused in reliance on the correctness of the identification. The judge should also direct the jury to examine closely the circumstances in which the identification was made. When the quality of the identification evidence is good, the jury can be left to assess the value of the identifying evidence even though there is no other evidence to support it. However, when the quality of the identifying evidence is poor, as for example when it depends solely on a fleeting glance or on a longer observation made in difficult conditions, the judge should withdraw the case from the jury and direct an acquittal unless there is other evidence that goes to support the correctness of the identification.
Code D of the codes of practice established under the Police and Criminal Evidence Act 1984 concerns the main methods used by the police to identify people in connection with the investigation of offences. These include video identification (where the witness is shown moving images of a known suspect, together with similar images of others who resemble the suspect); identification parades (where the witness sees the suspect in a line of others who resemble the suspect); and group identification (where the witness sees the suspect in an informal group of people). Code D also deals with identification by fingerprints; identification using footwear impressions; and identification by using body samples to generate a DNA profile for comparison with material obtained from the scene of a crime or a victim. See DNA fingerprinting.