Expert and specialist evidence and disclosure

1.There are three main types of expert used by HSE: specialist inspectors, experts from HSL and external experts. This section applies to all of them. The use of experts in HSE prosecutions is extremely common. However, it does raise specific issues in relation to the disclosure of material.

2. Material relating to the development of expert opinion is potentially disclosable and experts should keep any relevant material that they have in their possession in a suitable form for possible disclosure.  Specialist inspectors should use SIMPACT and HSL should use a comparable spreadsheet.  This may include both material they have generated themselves (notes, checklists, photographs, draft reports etc) and material obtained from third parties. The disclosure officer must ensure that this information is revealed to the prosecutor. Whilst the CPS has issued its own guidance to expert witnesses, HSE's guidance and instructions are contained in the Expert evidence section, this section and in the investigation operational procedures. However, especially when working with the police, inspectors should be aware that the CPS has its own forms for experts to complete and if the expert uses them, they can be accepted.

Experts' disclosure obligations

3. Once an expert has been appointed, s/he should be reminded that, as part of his/her duty to the court, s/he must assist in ensuring that the prosecution complies with its disclosure obligations. As with members of the investigating team, experts should be aware of the requirements to record, retain and reveal material in the course of preparing the report and giving expert evidence in court.  Experts should be aware of their duty to the court as set out in Part 19 of the CPR 2015.

Recording and retaining

When and how to record

4. Experts must begin to record relevant information from the date that they receive instructions. The duty to record continues for the entire period they are involved.

5. Records should be in durable form. Notes should be structured in a manner that facilitates review and any updates, alterations or comments should be clear. It is important that the notes are clear and comprehensive so as to allow anybody who subsequently reviews them to have a full understanding of the position at any given time. In particular, notes should be sufficiently detailed, and expressed in such a way, that other experts in the field are able to follow the nature of the work undertaken and to identify both any assumptions made and the inferences drawn from the work.

6. Records of communications between inspectors and experts should always indicate the date, the person(s) involved and a brief description of what was said. It is important that points of agreement (or disagreement) and agreed actions are recorded.

7. The format of record used will depend on the size and complexity of the investigation, but it might be:

  • a series of notes in a notebook;
  • a note in a dedicated log book; or
  • some other form of log.

What to record and retain

8. Experts should record all work carried out, and any findings reached, in relation to the investigation and prosecution case. They should be instructed to retain everything, including physical, written and electronically captured material, until otherwise instructed and the investigator has indicated the appropriate action to take. They should maintain a list of all material in their possession, and the disclosure officer should obtain this list when compiling the schedules and assess which material on it needs to be included in the schedules.  This may involve inspecting the material to assess its relevance.  Any material held by the expert which, in the opinion of the disclosure officer, satisfies the test for disclosure should be revealed to the prosecutor.

9. The following offers general guidance on material to be recorded and retained by an expert, but is not an exhaustive list:

  • Information relating to the chain of evidence
  • Details of any site visits and the examination of materials
  • Any notes used in the preparation of a report that contain primary facts not already recorded elsewhere, including any notes relating to preliminary conclusions;
  • Notes of speculative thinking, together with notes relating to preliminary conclusions and any other related notes;
  • All communications, verbal and written, with the inspector/investigating officer and any other relevant parties including e-mails and other electronic transmissions (eg images) sent or received. Correspondence between the expert and the inspector may be purely administrative in nature (for example, discussions regarding the payment of fees or an email asking when a report will be completed). As with similar material, this will not be relevant and need not appear on the schedules of unused material but that is for the disclosure officer to decide and the communications should nevertheless be retained;
  • Notes of meetings attended;
  • Clear notes of any witness accounts or explanations that the expert has been provided with, or any other information received; and
  • The results of all tests and not just those that support the prosecution case.
  • All material recovered and retained, together with evidence of continuity of handling.

How long to retain

10. As with all other material generated in the course of an investigation, the period of time for which expert materials are required to be retained will vary from case to case and will depend on a number of factors including the nature of the offence, the stage and status of any legal proceedings, and whether the case is of special interest. It must also be remembered that the retention requirement may alter as a result of a change of circumstances during the course of the investigation. See Period of retention for further guidance.

Revealing material

What to reveal

11. The expert is required to reveal to the disclosure officer all the material s/he has recorded. It is a necessary and important part of the expert's disclosure obligations to make the prosecution team aware of all the material that is in his/her possession in relation to the investigation. This will enable the disclosure officer to make informed decisions as to what material is relevant and whether it satisfies the disclosure test.  If the disclosure has not received this information by the time s/he is preparing the schedules, s/he should contact the expert to obtain it.

12. The expert has no role in determining what should be disclosed to the defence and s/he should follow instructions in relation to used and unused material. The disclosure officer will schedule the relevant material and apply the disclosure test. Any disclosure to the defence should be carried out under the guidance of the prosecutor, as the use of experts can lead to difficult disclosure issues. If necessary, the assistance of the prosecutor should be sought as early as possible.

13. All expert reports, other than the final one, should be identified by the expert as drafts, making it clear that they do not represent a final report (see Draft reports). Materials which may have some bearing on the offence charged, and the surrounding circumstances of the case, including the results of all tests, must be made known to the disclosure officer who must disclose them to the defence.

How to reveal

14. The expert's report or statement will set out his/her opinion and the material upon which s/he relies. In addition to the report, the expert should be asked to supply a list of any other material that s/he holds and which is not included in the list in the report, for example:

  • Administrative records detailing the transfer of samples or exhibits and instructions;
  • Notes;
  • Draft reports;
  • Correspondence including e-mails;
  • Minutes of conversations;
  • Databases;
  • Test results;
  • Material which the expert has decided to disregard; and
  • Any other material set out at paragraph 9.

15. This list will assist the disclosure officer in scheduling the unused material relevant to the case. The expert should remember that revelation to the prosecuting team does not necessarily mean disclosure to the defence.

Disclosure of the expert report

16. If the prosecution intends to rely on expert evidence, Part 19.3 of the Criminal Procedure Rules  requires disclosure of that evidence and associated material irrespective of the CPIA regime. This material should, however, be retained in the course of the investigation in accordance with the CPIA disclosure requirements. There are also provisions in Part 19.3 for the agreement of a summary of the expert's evidence.

17. The Criminal Procedure Rules state that a party who wants to introduce expert evidence must serve the court and each other party with the expert report as soon as practicable. (Rule 19.3). Rule 19.5 states that the expert must be informed of the service of the report at once. HSE expert reports will usually form part of the evidence bundle in any event.

18. In addition to the above requirement to provide the actual report, the party serving the report must serve with it notice of anything of which they are aware which might reasonably be thought capable of detracting substantially from the credibility of the expert (Rule 19.3(3)(c). In addition, the defence can make a request for a copy of (or to inspect) "a record of any examination, measurement, test or experiment on which the expert's findings and opinion are based, or that were carried out in the course of reaching those findings and opinion, and anything on which any such examination, measurement test or experiment was carried out." (Rule 19.3(3)(d)). It is also open to the prosecution to make such an application in respect of any defence expert. With regards to unused material, this entitlement is interpreted widely.

19. Where an expert report is to be used as part of the prosecution case, there are many types of material that might be relied upon or created and which may or may not be unused material that is potentially disclosable. These types of material can generally be placed in the following categories:

  1. Material provided to the expert by the inspector. This will usually, but not always, be the evidence upon which the prosecution relies;
  2. Other material the expert uses in completing the report, for instance established scientific findings or other published or unpublished texts, such as research reports, articles, codes of practice and guidance;
  3. Records of any observations, tests, calculations or other procedures which are not part of the final report (any such records that are part of the final report must, of course, be produced as part of the prosecution evidence);
  4. Draft reports or summaries thereof from the expert; and
  5. All correspondence or other communications passing between the expert and the inspector, for instance instructions to the expert and notes of telephone conversations, other than those between the expert and lawyers (which are legally privileged).

20. The defence is entitled to see any material provided by the inspector to the expert (category (1) material in the above paragraph). This will usually form part of the prosecution case and will therefore be provided to the defence in any event. However, where the expert has been provided with unused material, the defence, upon written request, will be allowed to see this material. This should not cause any difficulties as this material will have been scheduled as normal as part of the disclosure process. However, inspectors should be careful not to provide sensitive or privileged material (such as the investigation and prosecution reports, and legal advice) to an expert, as these will then be disclosable to the defence.

21. The Criminal Procedure Rules also allow the defence to see the material listed at (2) and (3) above. This material should normally be listed within the expert report and therefore disclosure to the defence should not cause any problems. Any such material should be scheduled as normal by the disclosure officer.

22. If an expert report is obtained but is not used as part of the prosecution case, it should be treated as any other document in accordance with the CPIA requirements on disclosure, that is scheduled, considered under the disclosure test and disclosed to the defence if appropriate. Any associated documentation, such as instructions to the expert, should be treated in the same way.

23. Draft reports (category (4) above) should be considered in the same way as other draft statements.

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Updated 2022-03-31