Home Office circular 057 / 2003

ADVICE ON THE USE OF VOICE IDENTIFICATION PARADES

Dear Colleague

ADVICE ON THE USE OF VOICE IDENTIFICATION PARADES

1. Further consideration has been given to the scope for developing voice identification procedures for use by police forces in England & Wales. Currently, Code D, paragraph 1.2, of the Codes of Practice under the Police & Criminal Evidence Act (PACE) 1984 allows for such procedures to be used, but does not specify which procedures must be followed.

2. This work to develop reliable procedures for voice identification, which may ultimately go forward for inclusion in Code D of the PACE Codes of Practice is on-going in consultation with relevant stakeholders. However, as there will continue to be cases from time to time where the police may wish to use such procedures, this Circular seeks to offer advice to forces through an example of good practice.

3. The procedures set out below for establishing a voice identification parade and generating admissible evidence were devised by DS McFarlane (Metropolitan Police) in order to bring a case to the Central Criminal Court in December 2002 (R v. Khan & Bains). The case was successful and both men were convicted, in small part, due to the voice identification evidence submitted, which was in turn commended by the trial Judge.

4. The Home Secretary has agreed that slightly amended procedures can be promulgated to forces, as an example of good practice, which have been tried and tested in the Courts and can be safely applied in similar, relevant circumstances.

5. The purpose of this Circular therefore, is to offer forces an example of good practice for advice and guidance. The procedures set out here are not mandatory, but it is recommended they be followed closely, as appropriate in the circumstances, where a voice identification parade is to be held by the force.

























PREPARATION OF MATERIAL

6. The identification officer in charge should obtain a detailed statement from the witness. This should contain as much detail and description of the voice as is possible (and should follow the guidelines handed down in R v TURNBULL 1977). All descriptions of the voice given by the witness must be included in the material supplied to the relevant forensic phonetics/ linguistics expert. The statement and any ‘first description’ of the suspect's voice should also be the subject of disclosure to the suspect/ solicitor prior to any identification procedure.

7. Under no circumstances should an attempt be made to conduct a live voice identification procedure, using live suspect and foils.

8. The identification officer should obtain a representative sample of the suspect's voice. A suitable source may be the police recorded interview tapes, during which the suspect is speaking naturally, responding to questions (although experts have advised the voice can be affected by stress). The suspect should be informed at the beginning of the interview that a sample of their recorded interview may be used for identification purposes and asked to give their consent. Experts in the field state clearly that under no circumstances should the suspect be invited to read any set text, as the speech/rhythm/tone may be unnatural and may well be altered by a person reading aloud from prescribed written material.

9. The identification officer should obtain no less than 20 samples of speech, from persons of similar age and ethnic, regional and social background as the suspect. A suitable source of such material may be other police recorded interview tapes from unconnected cases, either in-force or from other appropriate forces, e.g. where there is a strong regional accent.

10. The identification officer should ensure that all the work can be undertaken and completed within a reasonable time. It is advised that these procedures should be undertaken within 4-6 weeks of the incident in question, as memory degradation or 'fade' on the part of the witness has been identified as a critical factor by experts in the field.

11. The identification officer should request the services of a force approved expert witness in phonetics/ linguistics, for example, a Member of the International Association of Forensic Phonetics, to ensure the final selection and compilation of sample voices and match with the suspect's is as accurate and balanced as possible.

EXPERT WITNESS

12. The tape containing the sample of the suspect’s voice, together with the batch of ‘similar voices’ tapes should be passed to the commissioned expert witness. The identification officer should ensure that the suspect's tape is clearly marked as such. The remaining tapes should be marked, with the surname or custody reference number of the individual/ case concerned.

13. The expert should be commissioned to take selected samples of speech from the batch of tape sources. These should each be about one minute long, and may comprise various fragments of speech and/or continuous speech. It is irrelevant that each sample will contain different words or topics. A total of nine samples should be selected (i.e. the suspect’s plus 8 others).

14. These 9 speech samples should be recorded onto three video cassettes, each of which should have the samples in a different, random order. The samples should be numbered, with a visual (video) display of the number to accompany the sample. The identification officer must prepare an index for each video, detailing the name/reference of each sample and the allocated number. The three videos prepared should clearly be marked A, B and C. The reference number for each sample must be displayed on screen throughout the playing time of that particular sample. Each tape should contain three cycles of the samples.

15. The identification officer is responsible for ensuring, as far as is reasonable, that there is nothing within the selected samples which would lead to the identification of any individual or the offence which they were being questioned about. Each of the eight foil samples must be examined to ensure that the accent, inflection, pitch, tone and speed of the speech used, provides a fair example for comparison against the suspect. 1

16. It is strongly advised that the expert and identification officer conduct a number of test hearings, utilising mock witnesses, who are neither police officers nor connected with the suspect, where possible. These individuals should be given a brief resumé of the case. They should then be asked to listen to the series of samples under controlled conditions and asked to try and pick out the suspect for the offence (which they will only be able to do on a random basis or if there is a bias).

17. A further examination of all the samples against the results of the tests should be made to ensure that:
i. There is nothing contained in the words spoken, which would lead to an unfair assumption that one or other of the samples was that of the suspect;
ii. There is nothing in the manner of the speech, which would lead to an unfair assumption that one or other of the samples was that of the suspect.

18. These test results should form part of the evidence offered by the expert witness, demonstrating the objectivity of the procedures and the careful, balanced manner in which the procedures have been carried out.

19. The nine selected sample audio tapes should be sealed in one bag whilst the indices, placed in an envelope, should be placed in a separate sealed bag. Each bag must be signed and dated and an expert witness statement prepared, detailing the work undertaken in relation to the preparation of the material. The expert must present all the completed material, in sealed bags to the identification officer.

20. On completion of the preparation of the three sample video tapes and related indices, these must be sealed in police evidence bags by the commissioned expert carrying out the work.
21. The identification officer is responsible for the security and integrity of the material throughout the identification procedure process.


1. However, it should be noted that these procedures do not offer any opportunity for the suspect to review/reject any of the foil samples – but ref. Paragraphs 22 and 23







CONDUCT OF AUDIO/VOICE PROCEDURE

22. The suspect's solicitor must be given the opportunity to be present when the voice identification procedure is conducted. The seal on the bag of tapes must only be broken in the presence of the solicitor, if present, and the witness and the identification officer.

23. The identification procedure should be videotaped and the suspect given the opportunity to review at a suitable time after the procedure has taken place.

24. The solicitor should be given the opportunity to select the sample tape to be played (i.e. A, B or C). Throughout the process only the clearly marked identification letter will be used to refer to the samples.

25. The witness must be instructed by the identification officer that the voice of the suspect may, or may not be on one of the samples played during the procedure. The witness must be instructed to listen to each tape at least once before he/she makes a selection. The witness must be allowed to listen to any or all the samples as many times as they wish.

26. The identification officer must make a complete record of any comments or selections made by the witness.

27. Following the procedure a statement must be taken from the witness, recording the events and their selection. Once the witness has left the room the procedures were conducted in, the videotape should be left in the VCR machine/running. The identification officer should only then open the sealed bag and envelope, containing the index relating to the tapes and allow the solicitor the opportunity to record the details shown.

28. All materials relating to the procedure should be retained by the identification officer, for use in court.




These procedures are based upon procedures conceived originally by Detective Sergeant John McFarlane, Metropolitan Police Service, and are extended to all forces in England & Wales as an example of good practice, which has been tested and commended in court (Central Criminal Court, December 2002).




PLPU
Home Office
December 2003

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