IDG40220 - Sharing information outside of HMRC: procedural guidance: witness statements and affidavits
Source: gov.uk (2025-09-05)


When we disclose information to another person or organisation, that party may require the disclosure to take the form of a witness statement or affidavit.

A witness statement or affidavit is a formal document setting out the facts relating to a particular event.

HMRC information is often required by law enforcement agencies in order to build an evidential case for a prosecution. The information may be used in Court as evidence, or may only be required in the initial investigation and does not need to be formally presented as evidence before a court.

Whether the information is used or not, the investigator or the prosecutor may require the information to be set out in a formal, written, witness statement.

You should note that the supply of witness statements is not confined to cases connected with prosecutions under criminal law: information may also be requested or required in respect of disputes heard in the family and civil courts.

You may only provide information to third parties in the form of a witness statement if there is lawful authority to disclose this information, as provided by the Commissioners for Revenue and Customs Act.

This means that we may only provide information in the form of a witness statement:
- when disclosing through legal gateways to other public organisations (see IDG40320 (https://www.gov.uk/hmrc-internal-manuals/information-disclosure-guide/idg40320) for details of legal gateways), or
- when disclosing information with the consent of the individual who the information is about (see IDG30210 (https://www.gov.uk/hmrc-internal-manuals/information-disclosure-guide/idg30210) for disclosing with consent).
The HMRC officer making the witness statement may also be required to attend court to give evidence relating to its contents, under oath.

Procedure for handling witness statements or affidavits (#IDAFUN0I)Procedure (#IDA1QN0I)Child Benefit Office (#IDAOVN0I)Tax Credit Office (#IDA2SN0I)Risk and Intelligence Service (RIS) (#IDAWRN0I)Centre for Exchange of Intelligence (CEI) (#IDA3QN0I)Law Enforcement Operations (#IDATWN0I)Section 9 Criminal Justice Act 1967 statements (#IDAIXN0I)Further guidance (#IDA1XN0I)

Procedure for handling witness statements or affidavits

Who makes the witness statement?

Any permanent and established member of HMRC staff is permitted to produce and sign a witness statement provided that they have the lawful authority to disclose the requested information. It does not have to be the person who dealt with the matters which interest the court. However, as the person who makes the statement may be called to court to make the statement on oath, they must be someone who is familiar with the case, has sufficiently good knowledge of the subject and is prepared to attend court if necessary.

Should you have any concerns about completing a witness statement (or the possibility of attending court) you should speak to your manager in the first instance.

What should a witness statement contain?

Only information permitted in the terms of the CRCA may be included in a witness statement. This means you may only disclose information which either a customer has consented to disclose, or which is allowed by a legal gateway (see IDG40320 (https://www.gov.uk/hmrc-internal-manuals/information-disclosure-guide/idg40320)).

You should only disclose information that is relevant to the case.

The person requesting the statement will set out the issues that you will be required to cover in the statement. If you are in any doubt, you should ask the person requesting the statement to provide you with further information.

There are certain “rules of evidence” that the prosecution lawyers will deal with if the matter goes to court.

Unused material

If you provide a witness statement in a criminal matter, then any information which you hold and is relevant to the criminal investigation but which is not contained within the witness statement is “unused material”. An example of unused material may be notebooks that your witness statement is based on.

There are strict legal rules that govern unused material with obligations being placed on investigators and prosecutors. You should inform the relevant investigator if there is information or documents that are relevant to the investigation apart from your witness statement and any exhibits that are attached. In certain circumstances, this information may have to be disclosed to the defence and you should co-operate unless there are public interest immunity issues that may attach to the information (e.g. the information relates to, and identifies, a CHIS (covert human intelligence source)).The gateway for disclosure will normally be the same as the gateway through which the witness statement was provided, but if you have any queries you should contact your Security & Information Business Partner (SIBP) for further advice.

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Procedure

The following teams provide the majority of witness statements on behalf of HMRC:

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Child Benefit Office

Child Benefit Office (CBO) Customer Relations Unit have a process in place for providing witness statements: this is usually to the DWP or the Housing Benefits sections in Local Authorities. If you work in CBO and receive any request for a witness statement, please contact CBO Customer Relations Unit in the first instance (see IDG80100 (https://www.gov.uk/hmrc-internal-manuals/information-disclosure-guide/idg80100) for contact details).

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Tax Credit Office

Tax Credit Office (TCO) Multi-Agency Team have a process in place for providing witness statements to the DWP or the Housing Benefits sections in Local Authorities. If you work in TCO and receive a request for a witness statement, please contact TCO Multi-Agency Team in the first instance (see IDG80100 (https://www.gov.uk/hmrc-internal-manuals/information-disclosure-guide/idg80100) for contact details).

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Fraud Investigation Service (FIS)

HMRC’s FIS Team has sole responsibility for providing tax-related information to the DWP. This includes cases where information may be further disclosed to Local Authority housing benefit teams. If the DWP contact you and ask that you supply a witness statement or other information, you should refer the enquirer to the Specialist Witness Statement Unit (WSU) in FIS who will then determine what information can be disclosed.

Specialist Witness Statement Unit (WSU) in FIS also provide police forces and other law enforcement authorities (see IDG50110 (https://www.gov.uk/hmrc-internal-manuals/information-disclosure-guide/idg50110)) with information. With the exception of certain of HMRC’s own law enforcement activities, only this team is authorised to provide this type of information. If you receive a request for a witness statement from either the police or one of the law enforcement authorities listed at IDG50110 (https://www.gov.uk/hmrc-internal-manuals/information-disclosure-guide/idg50110), then you should contact WSU.

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Law Enforcement Operations

Witness Statements created in the course of our own or joint law enforcement operations have different procedures attached to them. This will affect mainly Criminal Investigation, Detection and Intelligence staff. Please see the enforcement handbook for more guidance on providing witness statements in these circumstances. This is accessible via a hyperlink found at IDG80300 (https://www.gov.uk/hmrc-internal-manuals/information-disclosure-guide/idg80300).

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Section 9 Criminal Justice Act 1967 statements

In criminal proceedings, you may be asked to provide a witness statement under the provisions of section 9 CJA 1967. This means that the statement will be set out in a particular, legally required, format and includes a declaration which you must sign and date along with each page of your statement. The purpose of a section 9 CJA statement is that if the matter goes for trial, and your statement is accepted by the other side, then it can be read out and you need not attend to give evidence. However, depending on the facts of the case and the importance of your evidence, the person relying on your statement may still require you to attend court and give evidence. Alternatively, your statement may not be acceptable to the opposing side and they can require you to give evidence.

If you are informed that your statement has not been accepted, then you should attend court when required to do so. You should inform the investigator of any dates that you cannot attend and also any other special requirements (for example, attending in the afternoon if you have a long journey to the court) and the court will try to accommodate your requirements as far as it reasonably can. You must also inform your line manager.

If you refuse to attend, or simply do not attend without reasonable excuse, then the court may issue a witness summons for your attendance or, if the court has already ordered your attendance, contempt proceedings may be brought against you.

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Further guidance

If you receive a request for a witness statement and, after reading this guidance and discussing the issue with your manager you are still unsure how to proceed please contact your Security & Information Business Partner (SIBP) for further advice.