Disclosure Manual: Chapter 5 - Reasonable Lines of Enquiry and Third Parties
Lines of enquiry
The duty under the CPIA Code of Practice to pursue all reasonable lines of enquiry, whether these point towards or away from a suspect, may extend to material in the hands of a third party.
What amounts to a reasonable line of enquiry will always involve considering the facts of, and the issues in, the case including any defence raised. It is important that any enquiry is proportionate, reasonable and necessary. This involves consideration of
- what is expected to be found through the enquiry, to determine what is reasonable in the circumstances;
- how best to seek that information/material, taking a proportionate approach; and
- being able to explain why it is needed.
Third party material is that held by a person, organisation, or government department other than the investigator or prosecutor. It may be held by those inside or outside of the UK. Frequently encountered third parties include:
- owners of CCTV material;
- social services departments;
- forensic experts;
- police surgeons; and
- GPs and hospital authorities.
The Joint Protocol between the Crown Prosecution Service and the Police on dealing with third party material (Joint Protocol) sets out the arrangements in respect of the investigation, the institution and prosecution of offences in which there is third party material and the relevant duties and functions of the investigator, the disclosure officer and the prosecutor. The Joint Protocol draws together the agreement to use the standard correspondence and forms on a national basis, namely;
- The letter to be sent to third parties asking them to identify material they may hold;
- A pro-forma reply for third parties to use to respond;
- An index of material requested;
- A viewing log of material inspected.
Where local protocols exist, for example, for social services material, prosecutors should access and handle material in accordance with its terms.
Regard must also be had to the 2013 Protocol and Good Practice Model on Disclosure of Information in Cases of Alleged Child Abuse and Linked Criminal and Care Directions Hearing (which provides the framework for the police and CPS to obtain disclosable material from local authorities, and for applications to be made to the Family Court, in cases involving children of 17 and under.
Prosecutors are reminded that prior to the service of the prosecution case, applications to the family court for disclosure of material will generally be made by the police. After this stage, applications will be made by the CPS.
A third party has no obligation under the CPIA to reveal material to the investigator or to the prosecutor, nor is there any duty on the third party to retain material which may be relevant to the investigation. In some circumstances, the third party may not be aware of the investigation or prosecution.
If the OIC, the investigator, or the disclosure officer believes that a third party holds material that may be relevant to the investigation, that person or body should be told of the investigation and alerted to the need to preserve relevant material. The disclosure officer should inform the prosecutor of the identity of the third party and the nature of the material the third party is believed to possess by way of the MG6. The defence should be informed of what steps have been taken to obtain relevant material and what the results of the enquiry have been, ideally in the DMD.
If relevant material held by third parties is inspected by the police but not retained, a record of its content must be made using the national template inspection log. Where the investigator has not obtained the material, the prosecutor should consider whether it is appropriate to advise the police to seek access to the material as part of their duties to explore all reasonable lines of enquiry.
If material relevant to the investigation is obtained from a third party, it will become unused material or information within the terms of the Code of Practice and must be handled accordingly.
Investigators, disclosure officers and prosecutors must also have regard to whether relevant material may exist in relation to other linked investigations or prosecutions. Reasonable enquiries must be carried out to establish whether such material exists and, if so, whether it may be relevant to the instant prosecution.
Considering whether enquiries should be made
The Attorney General’s Guidance on Disclosure 2022 outlines a three-step approach incorporating the requirements set out in R v Bater-James & Anor  EWCA Crim 790 when considering whether third party material should be requested:
- Establishing a reasonable line of inquiry
- Establishing relevance and
- Balancing rights
Step 1: Establishing a reasonable line of inquiry
Collecting or inspecting material from third parties must only be done when an investigator is pursuing a reasonable line of enquiry. In Bater-James and Another  EWCA Crim 790 Lord Justice Fulford stated at paragraph 70 of the judgement that “it is not a "reasonable" line of inquiry if the investigator pursues fanciful or inherently speculative searches. Instead, there needs to be an identifiable basis that justifies taking steps in this context. This is not dependent on formal evidence in the sense of witness statements or documentary material, but there must be a reasonable foundation for the inquiry.”
Investigators should not make speculative enquiries of other persons or agencies; there must be some reason to believe that the third party may hold relevant material. That reason may be informed by information provided to the investigator by the accused or from other enquiries made or from some other source. It bears repeating that relevant material is that which is capable of having some bearing on any offence under investigation or any person being investigated or on the surrounding circumstances, unless it is incapable of having any impact on the case. Investigators must be able to clearly articulate why it is a reasonable line of enquiry to obtain material in possession of a third party.
An assessment of reasonableness is required and must be made on a case-by-case basis. There are no standard enquiries which apply to cases or offence types. Regard should be had to the prospect of obtaining relevant material and what the perceived relevance of that material is, having regard to the identifiable facts and issues in the individual case.
When the third-party material in question includes personal data, investigators and prosecutors must refer to paragraphs 11-15 of the AG’s Guidelines to ensure that there is no unjust intrusion of privacy.
An investigator may seek the advice of the prosecutor when considering which lines of enquiry should be pursued. The 6th Edition of the Director’s Guidance on Charging (DG6) strongly recommends the provision of Early Advice in specific case types. During Early Advice investigators and prosecutors should discuss third party material and should agree what reasonable lines of enquiry need to be pursued based on the unique facts of the case. Where personal data is involved, consideration should be given to a targeted, focussed review to avoid excessive collateral intrusion. Obtaining Early Advice should assist an investigator in articulating to a third party why material needs to be obtained as a reasonable line of enquiry.
Investigators and prosecutors should adopt a ‘thinking approach’ as considered in the cases of R v Alibhai  EWCA Crim 681, and R v Flook  EWCA Crim 682. In Flook the Court found that there cannot be any absolute obligation on the Crown to disclose relevant material held overseas outside the European Union. The obligation is therefore to take reasonable steps to obtain the material.
Step 2: Establishing relevance
Third party material should only be requested in an individual case if it has been identified as relevant to an issue in the case. This will depend on the circumstances of the individual case, including any potential defence, and any other information informing the direction of the case. Paragraph 32 of the AG’s Guidelines lists factors that investigators and prosecutors should consider when deciding whether third party material should be requested in an individual case. This list is not exhaustive, and the considerations will vary depending on the circumstances of the case.
- What relevant information is the material believed to contain?
- Why is it believed that the material contains that relevant information? If it is likely that no relevant information will be contained within the material, a request should not be made.
- Will the request for the material intrude on a complainant’s or witness’s privacy?
- If the material requested does amount to an invasion of privacy, is it a proportionate and justifiable request to make in the circumstances of the individual case and any known issues? Consider vi. below or whether the information which may result in access amounting to an invasion of privacy can be redacted to remove anything that does not meet the disclosure test.
- Depending on the stage of the case, does the material need to be obtained or would a request to preserve the material suffice until more information is known?
- Is there an alternative way of readily accessing the information such as open-source searches, searches of material obtained from the suspect, or speaking directly to a witness, that does not require a request to a third party?
- Consider the scope of the material required, for example are the entirety of an individual’s medical records required or would a particular month or year be sufficient? Ensure the request is focused so that only relevant information is being sought.
- The process of disclosure and its role in the justice system should be clearly and understandably expressed to the third party. They must be kept appraised of any ongoing disclosure decisions that are made with regard to their material.
Step 3: Balancing rights
Paragraphs 11 to 13 of the AG’s Guidelines outline principles that investigators and prosecutors need to be aware of when both the right to a fair trial and the privacy of complainants and witnesses are engaged. Paragraph 13 contains the fundamental approach that must be adopted by investigators and prosecutors when deciding whether it is necessary to request and/or process personal or private information from a complainant or witness to pursue a reasonable line of inquiry.
The AG’s Guidelines recognises that in some cases the third-party material may reveal intimate, personal or delicate information. The disclosure test should be applied and if the material undermines or assists prosecutors should closely scrutinise it and only disclose it where absolutely necessary.
Investigators must clearly document their decision making in relation to reasonable lines of enquiry and third-party material, recording the grounds for pursuing a request to a third party. Prosecutors should utilise the DMD to ensure that the Court and Defence are informed of the position taken on Third Party Material, both in terms of requests made and decisions made not to request material.
Obtaining access to third party material
Before applying for a witness summons it may be appropriate to make a formal request directly to the third party. A third party will need to be mindful of their obligations under the Data Protection Act 2018 and the UK General Data Protection Regulation (UK GDPR) when processing data. It is therefore crucial that the formal request clearly articulates what material is required and that reviewing the material represents a reasonable line of enquiry. The principle of data minimisation should be considered and only material that represents a reasonable line of enquiry should be requested.
Where access to the material is declined or refused by the third party and the investigator believes that it is reasonable to seek production of the material before a suspect is charged because they believe it is likely to be relevant evidence and of substantial value, the investigator may consider making an application under Schedule 1 of the Police and Criminal Evidence Act 1984 (PACE), (Special Procedure Material), a search warrant and/or the Bankers Books Evidence Act 1879. The investigator may seek advice of the prosecutor before such an application is made.
Investigators and prosecutors should consider appropriate parameters when requesting material. The ICO provides detailed guidance for organisations processing data on its website. A suitable time should be given for a response before making an application for a witness summons. However, where a third-party refuse to co-operate, the prosecutor should consider whether to make an application for a witness summons (where proceedings are before the court and to do so is in the interests of justice). A prosecutor should only make an application where the statutory conditions are satisfied as set down in section 97 of the Magistrates' Court Act 1980 or in the Crown Court, section 2 Criminal Procedure (Attendance of Witnesses) Act 1965 as amended. Applications for witness summonses must be in accordance with the Criminal Procedure Rules (see 17.5 and 17.6).
The statutory requirements in section 97 of the Magistrates' Court Act 1980, and section 2 of the Criminal Procedure (Attendance of Witnesses) Act 1965 as amended, are more stringent than the disclosure test. The court may issue a summons if it is in the interests of justice and the person is likely to be able produce any document or thing likely to be material evidence. Accordingly, there should be consultation between the investigator and the prosecutor before any application to the court is made to assess whether it can properly proceed. (R v Brushett (2001) Crim LR 471, illustrates an approach, commended by the Court of Appeal, where a pragmatic and co-operative stance was taken by social services and material revealed to the prosecution).
If the prosecutor believes there is relevant material which the third party has declined to reveal, but grounds for witness summons are not made out, the prosecutor should notify the court and, where appropriate, the defence.
Where material is obtained from third parties, the investigator should discuss with them whether any sensitivities attached to the material that might influence whether it is used as evidence, or otherwise disclosed to the defence, or whether there may be public interest reasons that justify withholding disclosure. The third party's view must be passed to the prosecutor using the MG6D.
Section 63 of the Serious Organised Crime and Police Act 2005 is concerned with the production and retention of material obtained from third parties by way of a disclosure notice under section 60 of that Act. Full guidance on the power to issue a disclosure notice under the act can be found in the CPS legal guidance Director's Investigatory Powers.
In cases where the victim of a crime is an organisation or institution, it is likely that the organisation will hold both evidential and unused material. It is unsafe to assume that the marshalling of material may be left until after a charging decision has been made (as the organisation may not have fully considered the potential importance of its material to the case, and/or understood the obligations set out in the CPIA). A pro-active approach is required, with early engagement between the disclosure officer and organisation in question where possible. Further guidance for CPS prosecutors can be found in Disclosure where an Institution or Organisation is the Victim.
Material from Overseas
The obligations under the CPIA Code to pursue all reasonable lines of enquiry apply to material held overseas. Guidance on the obligations on the prosecutor in respect of material held overseas are set out in paragraphs 46 - 54 of the Attorney General’s Guidance on Disclosure 2022 ("International Enquiries").
See Chapter 35 on International Enquiries for details.
Government Departments and Public bodies as third parties
During an investigation or prosecution, it may become apparent that a Government department or another Crown body has material that may be relevant to an issue in the case. Where it appears to an investigator, disclosure officer or prosecutor that such material exists, reasonable steps should be taken to identify and consider such material. The investigator or prosecutor should inform the department or body at the earliest opportunity of the nature of the case and the relevant issues. They should ensure that they provide enough information to allow for the department or body to understand what may be relevant in the context of the request. Crown Servants have a duty to support the administration of justice and should take reasonable steps to identify and consider such material. This extends to revealing to the investigator or prosecutor the extent of the searches conducted and the existence of any information that they believe may be relevant to the issues in the case, to supply them with that information unless it is protected by law, subject to legal professional privilege or attracts public interest immunity.
If access is denied to the material, the investigator or prosecutor should consider the reasons given by the Government department or Crown body and what, if any, further steps might be taken to obtain the material. The final decision on further steps rests with the prosecutor.
Investigators and prosecutors cannot be regarded as being in constructive possession of material held by Government departments or Crown bodies simply by virtue of their status.
The steps taken to identify and obtain relevant material held by a Government department or Crown body should be recorded by the investigator and prosecutor. Where appropriate, the defence should be informed of the steps taken to obtain the material and the results of the line of enquiry. Ideally, this would be done in the DMD.