Employee interview notes produced during internal corporate investigations are among the most frequently contested privilege documents in modern litigation. Whether they are protected turns on a careful application of legal advice privilege and litigation privilege — two related but distinct doctrines — and on the particular facts of how the investigation was structured and conducted. This article explains the legal framework, the leading authorities, and the practical steps businesses should take to maximise their chances of retaining privilege over this sensitive category of material.
1. Why This Question Matters
When a compliance concern arises within an organisation — a suspected fraud, a potential breach of competition law, an allegation of regulatory non-compliance, or a whistleblower complaint — one of the first steps is almost always to interview relevant employees. Those interviews are conducted by lawyers, compliance officers, or external advisers, and the resulting notes or memoranda contain sensitive factual accounts that may be highly valuable to regulators, prosecutors, or adversaries in civil litigation. The question of whether those notes are legally privileged is therefore not an abstract one. It determines what can be compelled in disclosure, what documents must be handed over in response to regulatory demands, and what material a claimant or the Serious Fraud Office can require the company to produce.
The stakes are high. Interview notes from investigations routinely capture admissions, inconsistencies between accounts, assessments of credibility, and an organisation’s legal strategy. If they are not privileged, they may become the most damaging documents in the case. If they are privileged, they provide the legal team with a protected space in which to understand what happened and formulate an appropriate response. Understanding the law in this area is therefore essential for any business that takes compliance and investigation preparedness seriously.
2. The Two Heads of Legal Professional Privilege
English law recognises two distinct heads of legal professional privilege (‘LPP’). Both are potentially available for interview notes, but they operate on different principles and face different obstacles in the investigation context. It is important to understand each in turn before assessing how they apply to interview notes specifically.
Legal Advice Privilege
Legal advice privilege (‘LAP’) protects confidential communications between a lawyer and client made for the dominant purpose of giving or receiving legal advice, whether or not litigation is on the horizon. It is the older and in some ways more conceptually straightforward of the two forms of privilege. However, its scope was significantly curtailed by the House of Lords in Three Rivers District Council v Governor and Company of the Bank of England (No 6) [2004] UKHL 48, which held that, for the purposes of LAP, the ‘client’ is not the organisation as a whole but a defined subset of individuals authorised to seek and communicate with the lawyers on the organisation’s behalf.
The consequence for interview notes is severe: a note of an interview with an employee who was a witness to or participant in the underlying events will generally not attract LAP, because that employee is not ‘the client’ for these purposes — they are a source of information about the facts. The communication captured in the note is not a communication between the legal adviser and the authorised client; it is a communication between the lawyer and a third party or a non-client employee. This restriction severely limits the availability of LAP as a basis for protecting investigation interview notes in large organisations, particularly where numerous employees at different levels of seniority are interviewed.
Litigation Privilege
Litigation privilege (‘LP’) has a broader reach than LAP. It protects confidential communications between lawyers, clients, and third parties — including witnesses and experts — where two conditions are satisfied: first, adversarial litigation or proceedings must be reasonably anticipated or already on foot; and second, the dominant purpose of the communication must be to enable the lawyer to advise and act in those proceedings. Unlike LAP, LP expressly extends to communications with third parties, which means that employee interview notes can in principle attract LP even where those employees fall outside the narrow definition of ‘client’ under Three Rivers (No 6).
LP is therefore the primary basis on which businesses seek to protect employee interview notes generated in investigations. The availability of LP turns entirely on the two conditions above — the nature of the anticipated proceedings and the dominant purpose of the notes — and it is on these conditions that the most important legal disputes in this area have been fought.
3. The Landmark Authority: ENRC v Serious Fraud Office
Background and the Questions at Stake
The most important modern authority on this issue is Director of the Serious Fraud Office v Eurasian Natural Resources Corporation Ltd [2018] EWCA Civ 2006, a decision of the Court of Appeal that is essential reading for any business facing regulatory scrutiny. ENRC, a large mining company, had commissioned an internal investigation following concerns about potential bribery and corruption. External solicitors and forensic accountants were instructed. The investigation involved extensive employee interviews, producing a large number of interview notes and memoranda. When the Serious Fraud Office (‘SFO’) opened a formal investigation, it sought to compel ENRC to produce those interview notes and related investigation documents. ENRC resisted on grounds of LPP.
At first instance, Andrews J held that neither LAP nor LP applied to most of the interview notes. On appeal, the Court of Appeal (Sir Brian Leveson P, Gross and Flaux LJJ) allowed the appeal in part and significantly expanded the circumstances in which LP can protect internal investigation documents. The judgment is the leading English authority on the privilege status of investigation interview notes and deserves detailed analysis.
The Court of Appeal’s Reasoning on Litigation Privilege
The Court of Appeal made three findings of principle that significantly extend the scope of LP in the investigation context. First, it held that LP is not confined to civil proceedings. It can apply where criminal proceedings, regulatory enforcement action, or prosecution are reasonably anticipated, even if those proceedings have not yet been formally commenced. The court was unpersuaded by the SFO’s argument that LP requires a civil adversarial claim in the orthodox sense, holding that what matters is whether the proceedings, when they materialise, will be adversarial in character. Regulatory enforcement action by the SFO, the Financial Conduct Authority, or analogous bodies plainly satisfies this requirement.
Second, the Court of Appeal held that the threshold for ‘reasonable anticipation’ of litigation is lower than Andrews J had suggested. An organisation need not be in the position of a defendant who knows that a claim is coming. It is sufficient that there is a reasonable and objective basis for anticipating adversarial proceedings at the time the documents are created. In the context of internal investigations prompted by bribery allegations, whistleblower reports, or the opening of a regulatory inquiry, it will very often be the case that prosecution or enforcement action is reasonably to be anticipated from the outset of the investigation.
Third — and most significantly for present purposes — the Court of Appeal held that interview notes and investigation reports prepared in these circumstances can be protected by LP, provided that the dominant purpose test is satisfied. The dominant purpose of the interview notes in ENRC was held to be preparation for anticipated adversarial proceedings: the lawyers needed to understand what had happened so that they could advise the company in relation to the reasonably anticipated investigation and any proceedings that might follow. That, the court found, was a sufficient purpose to engage LP.
The Limits of the ENRC Decision
It is important not to overstate what ENRC decided. The Court of Appeal did not hold that all investigation interview notes are automatically privileged. Several important limitations remain. The court confirmed that LP does not apply where the dominant purpose of the investigation is a general business or compliance review, as opposed to preparation for anticipated adversarial proceedings. If an organisation conducts employee interviews primarily to understand its operations, to implement a new compliance programme, or to satisfy a regulatory reporting obligation (rather than to prepare for proceedings), the dominant purpose requirement may not be met and LP will be unavailable. The purpose question is intensely fact-specific and will depend on the circumstances in which the investigation was commissioned, the instructions given to lawyers and investigators, and the nature of the concern being investigated.
The decision in The RBS Rights Issue Litigation [2016] EWHC 3161 (Ch), decided before ENRC at first instance, illustrates the danger of assuming that privilege will attach. In that case, Hildyard J held that interview notes produced during an internal investigation into RBS’s capital raising were not privileged, because the investigation had been conducted primarily for regulatory and commercial purposes rather than in genuine contemplation of litigation. The dominant purpose of the interviews was to report to the Financial Services Authority, not to prepare for proceedings that were then not reasonably in view. The case is a reminder that courts will look carefully at what the investigation was actually for, rather than what it is characterised as in retrospect.
4. The Dominant Purpose Test in Detail
The dominant purpose test is the central battleground for privilege disputes over investigation interview notes. English courts have made clear that LP requires a single ‘dominant’ purpose, not merely a significant or substantial one. Where interview notes are prepared for multiple purposes — for example, both to advise on litigation exposure and to facilitate a regulatory disclosure or remediation programme — the court will ask which purpose was the driving reason for the creation of the document. If advising on anticipated litigation was the predominant reason, LP will apply. If it was a co-equal or secondary reason, LP will not apply to the document as a whole, although it may be possible to redact the genuinely privileged elements if they can be meaningfully separated from the non-privileged material.
Determining dominant purpose requires an objective assessment of all the circumstances. Courts will examine the instructions under which the investigation was commissioned, contemporaneous correspondence and retainer letters, the context in which the interviews were conducted, whether legal advisers were present, and what the resulting notes were used for. The mere fact that lawyers conducted or supervised the interviews, or that the notes were marked ‘privileged,’ does not conclusively establish LP. Courts in privilege disputes — which are often conducted on the basis of written submissions and redacted samples rather than full disclosure — will be alive to the risk that businesses seek to cloak otherwise unprotected fact-finding in a privilege label after the event.
Timing is also relevant, though not determinative. An investigation commissioned at a time when no complaint has been received, no regulatory inquiry is under way, and no specific allegation has been made will face a higher burden in establishing that litigation was reasonably in contemplation. An investigation triggered by a specific allegation, the receipt of a formal regulatory notice, the opening of a criminal inquiry, or credible whistleblower evidence of serious wrongdoing will be in a much stronger position. The ENRC case established that it is not necessary to wait until a formal claim or charge is issued before LP can bite — an objective and reasonable apprehension of adversarial proceedings is sufficient — but the more concrete the threat of proceedings at the time the interviews were conducted, the more readily the court will find the dominant purpose condition satisfied.
5. Why Legal Advice Privilege Is Rarely Sufficient for Interview Notes
As noted above, the Three Rivers (No 6) definition of ‘client’ creates a significant obstacle to using LAP to protect employee interview notes in large organisations. The decision has been widely criticised — the Law Commission itself described aspects of the reasoning as problematic — but it remains binding authority in England and Wales. Its practical effect is that where lawyers interview employees who were actors in or witnesses to the underlying events (rather than specifically authorised to instruct or communicate with legal counsel), the resulting notes are not LAP-protected, because the communication is not between lawyer and client in the relevant sense.
This conclusion holds regardless of how senior the employees are, or how closely their accounts bear on the legal advice subsequently given by the lawyers. A note of an interview with a Chief Financial Officer about his knowledge of the transactions under scrutiny will not attract LAP if the CFO was not specifically authorised as part of the ‘client’ group for the purposes of the investigation, even though his account is of central importance to the legal advice the company receives. This seems a harsh and formalistic result — and was one reason why the courts and practitioners welcomed the ENRC Court of Appeal’s expansive approach to LP as the more flexible and workable basis for protecting investigation documents.
One partial solution is to structure the investigation so that a small, specifically authorised ‘client group’ — perhaps the board’s Audit Committee, a Special Committee, or the General Counsel together with two or three board members — is identified as the body instructing the lawyers. Communications between those individuals and the investigating lawyers can then be brought within LAP. The employee interviews themselves, however, will generally need to be protected, if at all, under LP, which requires the litigation threshold to be crossed.
6. Waiver, Deployment, and the Risk of ‘Cherry-Picking’
Even where privilege over interview notes is properly established, it can be lost through waiver. Waiver can be express — where the organisation voluntarily discloses the notes to a regulator or third party — or implied, where it deploys privileged material selectively in a manner that would be unfair to its opponent. The principle against ‘cherry-picking’ is firmly established in English law: a party cannot rely on part of a privileged document or class of documents to advance its own case while shielding the remainder from inspection. If an organisation refers to its investigation findings to assert, for example, that it found no evidence of wrongdoing, a court or regulator may well conclude that it has implicitly waived privilege over the underlying interview notes from which that conclusion was drawn.
This issue is particularly acute where organisations produce investigation reports to regulators as part of a cooperative approach to enforcement. There is a meaningful difference between producing a high-level summary of findings (which may or may not waive privilege over the underlying notes, depending on the level of detail and the terms on which it is shared) and producing the full investigation report or the underlying interview notes themselves. Where regulators are offered or demand sight of the notes, organisations should consider carefully whether a limited waiver can be agreed — for example, a waiver limited to the specific regulatory proceeding and not extending to third-party civil litigation — before making any disclosure.
Disclosure to external auditors, insurers, or joint venture partners presents similar risks. Some common law jurisdictions recognise a ‘limited waiver’ doctrine, under which disclosure on a confidential basis in pursuit of a shared common interest does not destroy privilege as against the rest of the world. However, English law on this point is less settled than, say, US law on joint defence privilege, and organisations should not assume that disclosure to third parties on a ‘without prejudice’ or ‘confidential’ basis will always preserve the privilege. Legal advice should be obtained before sharing investigation materials with any external party.
7. The US Position: The Upjohn Decision
For multinational businesses with US operations, it is worth noting that the American approach to privilege for investigation interview notes is in some respects more protective than English law. The Supreme Court of the United States in Upjohn Co v United States 449 US 383 (1981) rejected the narrower ‘control group’ test (which had limited corporate privilege to communications with senior management) and held that the attorney-client privilege can extend to communications between company lawyers and employees at all levels of the organisation, provided the communication was made at the direction of counsel, the employee understood the purpose was legal advice, and the substance of the communication related to the employee’s duties.
The Upjohn holding is more generous than the Three Rivers (No 6) approach in the sense that it does not confine the ‘client’ to an authorised subset of senior managers. However, US law has its own tensions: courts continue to grapple with what it means for counsel to be providing legal, as opposed to business, advice, and with the scope of the work product doctrine (the US equivalent of litigation privilege) in the context of dual-purpose investigations. Moreover, a key principle confirmed in Upjohn is that the privilege belongs to the corporation, not to the individual employees interviewed. This means that the corporation can waive the privilege and disclose the interview notes without the consent of the employees whose accounts they contain — a point with significant implications for how employees should be advised at the outset of an interview.
8. Practical Steps to Protect Privilege Over Interview Notes
Given the complexity of the law, there is no absolute guarantee that interview notes from an internal investigation will be held to be privileged. However, the following measures significantly improve the prospects of a successful privilege assertion and reduce the risk of inadvertent waiver.
Engage Lawyers at the Outset and Define Their Role Carefully
Legal privilege attaches to communications made for a legal purpose. The investigation should be commissioned by, or as soon as possible handed to, qualified lawyers — whether in-house (if their role can be clearly framed as legal rather than managerial) or external counsel. The retainer letter or terms of engagement should explicitly state that the purpose of the investigation is to enable the provision of legal advice and/or to prepare for reasonably anticipated adversarial proceedings. A generic ‘fact-finding’ mandate will not provide a strong basis for LP. If a specific allegation, complaint, regulatory notice, or credible whistleblower report has been received, this should be documented as the trigger for the investigation and the reason why litigation or enforcement action is apprehended.
Give Upjohn Warnings at the Start of Each Interview
At the outset of each employee interview, the lawyer conducting the interview should give what is commonly called an ‘Upjohn warning’ (after the US Supreme Court case) or, in an English context, an equivalent explanation. The employee should be told clearly: that the lawyers represent the company, not the individual employee; that the interview is being conducted to enable the lawyers to provide legal advice to the company; that the communication is confidential and privileged; but that the privilege belongs to the company and may be waived by the company at its discretion. The employee should be advised that they may wish to seek independent legal advice. These warnings serve two functions: they support the characterisation of the interview as a legal rather than a commercial or HR exercise, and they ensure that the employee understands the nature of the process, which is important for managing expectations about the confidentiality of their account.
Mark All Notes and Reports Clearly as Privileged
All interview notes, draft reports, and final investigation memoranda should be marked at the outset as ‘Privileged and Confidential — Prepared for the Purpose of Legal Advice and Anticipated Litigation.’ This labelling is not conclusive — a court will look at substance — but it is an important indicator of intent and helps ensure that the documents are managed consistently as privileged material within the organisation’s document management systems. Notes should be stored separately from general HR or compliance files and access should be restricted to those with a genuine need to review them.
Ensure the Notes Reflect the Lawyer’s Analysis, Not Merely Raw Facts
There is a meaningful distinction, recognised in the case law, between a bare transcript of what an employee said — which is more akin to a factual record that does not obviously attract privilege — and a note that reflects the lawyer’s analysis, selection, and assessment of the evidence gathered. Interview notes that record verbatim answers to questions in a mechanical way may be more vulnerable to challenge than notes that are organised around the legal issues identified by the lawyer and that capture the lawyer’s judgment about the significance of what was said. This does not mean that interview notes should be falsified or that important factual content should be obscured; rather, the form in which notes are prepared should make clear that they are the product of legal thinking, not merely a clerical record.
Be Cautious About Sharing Investigation Materials
As discussed above, any voluntary disclosure of interview notes — whether to regulators, auditors, insurers, or business counterparties — carries a risk of waiving privilege. Before any such disclosure is made, the organisation should seek specific legal advice about whether privilege will be lost and on what terms. In dealings with regulators, it may be possible to negotiate a limited waiver that preserves privilege in other proceedings. Agreements on the terms of disclosure should be reduced to writing. Particular care should be taken where disclosure is made to regulators in multiple jurisdictions, since the law on waiver varies significantly between legal systems.
Advise Employees Appropriately
As the Upjohn warning makes clear, employees should understand that they are not the privilege holder and that the organisation may disclose the interview notes without their agreement. At the same time, employees who may themselves face personal liability — criminal exposure, regulatory action, or civil claims — should be encouraged to seek independent legal advice before participating in an interview. An employee who participates in an investigation interview without independent advice may later argue that they were misled about the confidentiality of their account, which can generate its own legal complications. It is better practice to address these issues transparently at the outset.
9. Recent Developments and Continuing Uncertainty
The ENRC decision left a number of questions open and the law continues to develop. Most significantly, there remains uncertainty about how far ENRC’s expansive approach to LP can be pushed where the investigation is primarily reactive to regulatory expectations rather than driven by a genuine apprehension of adversarial proceedings. Regulators — particularly the SFO and the Competition and Markets Authority — have shown a consistent willingness to challenge privilege assertions in relation to investigation materials, and the courts are increasingly required to adjudicate these disputes. The SFO has indicated that it will continue to press the limits of ENRC, and subsequent first-instance decisions have not always interpreted that case as generously as might have been hoped.
There is also an ongoing debate about the relationship between LP and the right to a fair trial. The European Court of Human Rights has recognised the importance of LPP as an aspect of the right to a fair hearing under Article 6 of the European Convention on Human Rights, but has also left room for proportionate regulatory access to privileged material in appropriate circumstances. While absolute privilege remains the position under English law and the courts have repeatedly declined to introduce a balancing exercise, the expansion of regulatory power and international cooperation in enforcement means that the practical protection afforded by domestic privilege is increasingly tested by foreign proceedings and multi-jurisdictional investigations.
The growth of recorded communications in corporate life — emails, instant messages, collaboration platforms, recorded video calls — also raises new questions about interview notes in a broader sense. Where lawyers conduct remote interviews and those interviews are automatically recorded, the question of whether the recording itself (as opposed to a note of it) is privileged requires careful analysis. Recording may facilitate accuracy but can create a more ‘raw’ document that looks less like a lawyer’s analytical product and more like a factual transcript. Organisations planning investigations should think carefully about their note-taking and recording practices in light of these considerations.
10. Conclusion
Employee interview notes produced during internal investigations can be covered by legal professional privilege, but whether they are protected is not automatic and depends on a careful analysis of the facts. Legal advice privilege will generally not protect interview notes in large organisations because of the restrictive definition of ‘client’ established by the House of Lords in Three Rivers (No 6): employees who are sources of factual information are typically not the ‘client’ for LAP purposes, however senior or centrally involved they are.
Litigation privilege, as interpreted and expanded by the Court of Appeal in ENRC, offers a more powerful basis for protection. Provided that adversarial proceedings — civil, criminal, or regulatory — are reasonably anticipated at the time the notes are created, and provided that the dominant purpose of the interview and the resulting note is to prepare for or advise in relation to those proceedings, LP can and should apply. The ENRC decision is a significant development that aligns English law more closely with the practical reality of how regulated businesses operate, but it does not render investigation interview notes automatically privileged, and the dominant purpose test remains a live and frequently contested issue.
Businesses that take the practical steps described in this article — engaging lawyers early, documenting the litigation rationale, giving Upjohn warnings, marking documents carefully, and managing disclosure rigorously — will be in a materially stronger position to assert and maintain privilege over their investigation materials when it matters. Given the consequences of getting this wrong, the investment in privilege planning at the investigation design stage is invariably worthwhile.
This article is for general informational purposes only and does not constitute legal advice. The privilege status of any specific document or class of documents is a highly fact-specific question on which specialist legal advice should be sought. The law discussed is that of England and Wales unless otherwise stated.