Giving Evidence

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Evidence gathered during the course of a corporate investigation may be adduced in a range of different proceedings. They can broadly be split between administrative proceedings, or non-judicial proceedings and judicial proceedings, the legal forum. These include, but are not limited to:

  • Internal disciplinary proceedings
  • Regulatory Proceedings, for persons in the regulated sectors
  • Arbitration proceedings
  • Civil proceedings
  • Criminal proceedings
  • Employment law proceedings
  • Government enquiry proceedings

Each country operates its own legal system. Corporate and non-governmental organisation (NGO) investigators will broadly encounter two systems, namely, adversarial and inquisitorial. It is important the rules of evidence for the jurisdiction in which the evidence is being adduced are followed. Investigators in doubt about the rules of evidence in the jurisdiction in which they operate or are visiting should seek the appropriate internal or external legal advice.

Witness evidence may be heard, orally, or read in court or a legal forum such as an employment tribunal or administrative setting where the evidence will be weighed and tested independently. Such legal processes may require case witnesses to give evidence, usually under some form of oath or other affirmation of truth. Typically witness evidence will be read where it is agreed, or where the written evidence has been admitted as ‘hearsay’.

In a criminal case the need for witnesses to provide sworn oral testimony typically follows a ‘not guilty’ plea after which a date is set for a full court hearing. Formal hearings at employment tribunals are often intended to challenge a disciplinary sanction such as dismissal. Simply understanding the context giving rise to formal legal proceedings and the forum in which it is to take place may inform the investigator as to those areas of contention likely to be explored by legal representatives, e.g. whether there is a challenge to the witness’s account of events, or whether there are allegations of investigative bias, abuse of employment rights or disciplinary process?

The requirement for witnesses to give formal testimony serves to highlight the importance of having sound, legally-validated investigative procedures and evidence collection methodologies in place from the outset of an investigation. The use, for example, of legally approved real-time audio or video recorded witness and subject interview procedures, if permissible, provides less opportunity for subsequent legal challenge as the complete and original interview record is available. However, an investigator may be required to produce the interview record as an exhibit by confirming its origins, accuracy and integrity to the court or legal forum.

What is evidence?

Evidence is the information which is used in a court of law or other proceedings to determine whether or not something has happened. It is used to support or refute arguments. It is anything that you see, experience, read, hear or are told. Typically evidence is categorised as real, oral or documentary.

Real or tangible evidence

This is usually a material object of some kind, which is produced for inspection, either to prove that it exists, or so that the court can make an inference as to its condition or value, e.g. ripped clothing, a knife or burnt documents. It is normally produced to show that it exists or so that an inference can be drawn from its physical properties or condition. Real evidence includes material objects, the appearance of people or photographs, and so on.

Oral testimony

The oral statement of a witness made on oath or affirmation in open court and put forward as evidence of its truth. The parties to the court proceedings will usually give oral evidence in open court, as will any witnesses who are called to provide evidence. Whilst oral evidence is critical in court proceedings, there are clear legal rules governing what is admissible in court. Oral testimony must always be relevant to the case and legally admissible.

Documentary evidence

Documents including digital records of communications may be produced as evidence to a court. This category can be wide-ranging and may include any documents or written records that help prove or defend a claim or allegation. This may encompass an organisation’s policies and procedures, training records, work accident logbooks, financial records, diary entries, calendars, spreadsheets, employment contracts, attendance records, pay slips, phone records and organisational emails. It may include audio recorded interviews or interview notes made in the course of an investigation.

Corporate investigators, regardless of the nature of the proceeding, may be required to put their evidence into writing. In different jurisdictions the recording of this evidence can take different forms. It can include written witness statements, affidavits, or depositions. Much depends on the jurisdiction and nature of the proceeding in which it is contemplated the evidence will be adduced. In some jurisdictions it is becoming increasingly common for witness interviews, depositions and testimony to be recorded on video. Investigators should acquaint themselves with the methods of giving evidence in the types of proceedings in the jurisdictions in which they are required to undertake investigations. It is not ‘one size fits all’.

Witness statements

A witness statement is a true, accurate and relevant account of a witness’s evidence as to the facts within their knowledge. A witness statement must be based upon the witnesses’ own knowledge of the facts and not conjecture. Evidence of opinion is not generally admissible, though expert opinion, e.g. from a doctor, forensic scientist, accountant or engineer may be permitted by a court where the matters dealt with fall outside general knowledge and experience.

In many jurisdictions it is possible for the evidence contained in a witness statement to be agreed prior to the commencement of proceedings, i.e. where the opposing parties accept the contents of the statement. This procedure obviates the need for a witness to appear in person and greatly reduces the time taken and costs required in hearing a case.

Hearsay evidence

Hearsay evidence is where a witness in proceedings seeks to give evidence of a particular fact based on what was said to him or her by a third party. It is second-hand evidence and is not always admissible in court. However, there are exceptions, such as where the maker of the statement of fact is dead or otherwise unavailable. A court will carefully weigh the value of hearsay evidence according to the circumstances in which it was received and against the other evidence.

Many jurisdictions are more ready to admit hearsay evidence.


It is good practice to gather and prepare evidence to the same level as that required in a court proceeding. Robustly correct handling and procedural control of exhibits will allow them to stand up to scrutiny.

Documentary or real evidence used in a case needs to be attributed to a witness and if it is to be used in evidence it must be produced by a witness as an exhibit. The exhibit will be owned’ by the producing witness. Exhibits obtained from an employee or member of staff, such as security staff or HR personnel, will be their exhibit and will be marked and produced accordingly, even if another witness also refers to that exhibit in their own evidence.

It is good practice to identify exhibits by a label or other identifiable mark which includes a sufficient description to identify the contents. The initials of the witness producing the exhibit should also be included on the label followed by a consecutive number for each exhibit attributed to them in the case. This number and description must then be referenced in a statement by the exhibiting party outlining what the exhibit is, where it was located, when it was retrieved or gathered and who it has been given to. An example of such may be ‘Exhibit KEJ/1, a recorded copy of CCTV downloaded from the corporate internal system on Saturday June 20, 2021’.

Evidence and exhibits gathered during the course of an investigation, whether relied on in evidence or not, should be kept securely and you must ensure that there is a clear, identifiable audit trail from the moment that the exhibits are retrieved until they are used in a process or handed over to law enforcement. This ‘continuity of evidence’ process is vital as it may be required to demonstrate the authenticity and integrity of exhibits. A solid evidential audit trail can refute claims of evidence tampering.

Corporate documents

It is possible during corporate investigations or internal hearings that those involved may subsequently cast doubt on the company’s own records, e.g. articles of incorporation, office holders and annual statements of account. These documents may be particularly relevant in cases of fraud or financial misconduct. In such instances it is good practice to ask a company director to confirm their authenticity and correctness via a witness statement. In the UK certified copies of records submitted to UK Companies House may be required.

Computer records

Computer generated evidence may be either real evidence or hearsay. Evidence which has been electronic in source, process and result, with no human intervention in the process, may be considered real evidence and presumed reliable. It may however still be necessary to provide additional evidence from the relevant employee or, if more suitable, an expert witness to describe the function and operation of the equipment before the judge or decision maker can decide whether the document is real evidence or hearsay. Information extracted from a computer by a forensic IT specialist and used in court typically require that information to be exhibited or ‘proven’ as authentic, reliable and unmodified by the expert making the retrieval.

Evidence of previous character

There may be occasions where investigators may be approached by colleagues or other employees wishing to provide statements about a person’s character as evidence. Such statements may be general in character or contain clear assertions of fact.

Evidence of previous character is often not admissible in criminal proceedings. Evidence of pattern of behaviour by the subject in the case may provide an exception. An example of this may involve internal records of previous allegations or findings, previously imposed disciplinary sanctions for infractions of a similar nature and the reasons for these being imposed. The records may provide an investigatory lead, but will probably need to be substantiated by admissible evidence of the matters contained in them. Nevertheless, investigators should proceed with caution and ensure that any such evidence is relevant and compelling, otherwise investigators risk clouding a case with arguments about historical matters that bring little or no evidential benefit.

The duties of a witness

  • Witnesses have a duty to the court that overrides any obligation to the person who is instructing or employing them. Witnesses must act independently and be honest, truthful, trustworthy, objective and impartial.
  • When giving evidence a witness must provide an honest answer, regardless as to whether it supports a particular side or not. Indeed, lying under oath is perjury, a very serious criminal offence in almost all jurisdictions.
  • You must not allow your personal views about a person, organisation or case to affect the evidence you give.
  • Witnesses have obligations throughout the entire legal or administrative process, such as cooperating with case management hearings and adhering to timelines for reports and statements.
  • When giving oral evidence or writing reports, a witness must restrict their statements to areas in which they have relevant specific knowledge, or, if asked professional or expert questions, only around their areas of direct experience.
  • Any written statement or oral evidence provided must be accurate and not misleading. This means you must take reasonable steps to check the accuracy of any information you provided and to ensure all relevant information is included.
  • Where it is possible to do so, without misleading anyone, witnesses should use plain language and terminology that is easily understood. Any abbreviations or other technical terms must be explained.
  • Regardless of the pressure applied by a questioner, the witness is obliged to state only the facts that are in their possession and not to transgress from the truth for any reason.
  • If asked about facts that you do not know, then the witness should say that they do not know. This is a perfectly proper answer if it is an honest one. Witnesses should avoid providing an inaccurate or untruthful answer simply to escape what may feel like a barrage of questioning. It is perfectly acceptable, to simply repeat that you do not know.

How to give evidence

Wherever you are giving evidence, whether that is in a professional disciplinary hearing, administrative proceeding, employment tribunal or a court of law, there are practical points that remain constant. Providing a court or panel with strong evidence occurs when you feel natural, comfortable and at ease. In all circumstances in which you give evidence, consider the following:

  • Practical preparation is essential. Ensure that you know where and when you are required to give evidence and arrive in plenty of time in smart, appropriate dress. If necessary, familiarise yourself with the particular setting and establish how the court is to be addressed. In criminal settings, each court judge or bench will have specific means of address. If in doubt, or you are unable to clarify the correct terminology, a simple ‘Sir’ or ‘Madam’ will be appropriate. Take advice on the correct address of the officials in the proceeding; some jurisdictions have strict procedural rules relating to addressing parties to the proceedings. Professional investigators should understand the protocols for the proceedings in the jurisdictions in which they operate.
  • Be aware that as an investigator you may also be required to give informal support to counsel, prosecutor, or other parties to the proceedings, such as answering last-minute queries, checking that all required witnesses are present and are appropriately informed and guided throughout the process.
  • Your witness statement will form the basis for the questions that you will be asked when giving evidence. You should be thoroughly familiar with your evidence and should read your statement, and any related documents such as your exhibits, before going into the witness box or hearing room. Read and re-read it several times. You should also be attuned to any information that may indicate a challenge your evidence in cross-examination. You will not usually have access to your statement whilst giving evidence unless it was made shortly following an incident and you need to refresh your memory from it. You may only refer to your statement after seeking the permission of the court should clarification be needed around certain points. Access to your written evidence varies from jurisdiction to jurisdiction. In some jurisdictions, such as the US, pre-trial witness preparation by prosecutors forms part of the pre-trial process.
  • You should have in your possession any original notes you may need to refer to refer and any exhibits which you will produce. Again, the permission of the court is required in order to refer to them.
  • It is important, when giving evidence, to take your time and speak clearly and slowly. In particular, avoid using jargon and technical terms, or if you must, explain the meaning of jargon or technical terms. Do not be disturbed by members of the court making notes as this is quite normal. Temper your pace to present your evidence a calm and measured manner.
  • Depending on the setting of the court or hearing, you may not have a microphone available. Your delivery and your voice pitch should be adjusted according to the technical facilities and acoustics of the environment.
  • Be aware that non-verbal communication is also observed in evidential proceedings. It is therefore extremely important to ensure that you do not tut, roll your eyes, shrug your shoulders or use any negative form of body language to express frustration, outrage or negativity when you disagree with a point being made. Remain calm and professional throughout your giving your testimony.
  • Always direct your evidence to the bench or adjudicating official or officials. When positioning yourself in the witness box, direct your body towards the judge, jury, bench or panel, this will ensure your body naturally aligns in that direction. When a question is asked, face the questioner and listen carefully to the question. When answering, direct your attention and testimony once again to the bench, thereby indicating your readiness for the next question. This allows you to control the speed of questioning and avoid being distracted by the questioner who may use body language to try and draw you into presenting a negative impression of yourself.
  • If you do not understand a question you are entitled to get clarification from the questioner before answering. You may politely ask for it to be re-stated or re-phrased. Once you have commented it is harder to then retract or correct your response even if it was said due to a misunderstanding. It is therefore always preferable to ensure a question is clearly understood before answering.
  • Although summary evidentiary papers may have been prepared to assist the judge, adjudicator or panel in understanding a case in advance, you should not assume when you are giving evidence that all the evidence has been read or fully understood. Take every opportunity to assist the court by providing full, complete and relevant answers to questions to help the court determine its findings.


Cross-examination of a witness will often use a variety of techniques in an effort to diminish the value of oral testimony. For example:

  • Seeking to undermine witness evidence by attacking the witness’s reliability, such as finding an error and exploiting it to make their testimony appear unreliable.
  • Attacking the character of a witness, for example, making the witness appear biased or antagonistic towards a party, or highlighting what are said to be untruths in the witness’s evidence.
  • Offering an alternative explanation, known as a challenge, of what happened, sometimes presented as, “I put it to you…” or a similar form of words.

In court hearing the opposing party’s lawyer or representative may seek to draw an incautious reaction from a witness. Do not argue with the lawyer regardless of their tone or possible rudeness. In remaining calm you not only allow the focus to remain on the evidence that you are giving, but you also reduce the opportunity for demeanour or personality traits to be exploited in a way that may undermine your evidence.

Expert and professional witnesses

Professional witnesses, such as investigators, provide evidence of their investigative findings, observations and actions and the reasons for them. As a witness of fact, your written and oral evidence should be clear and concise and be based on investigative records and notes made at the relevant period.

On the other hand, the role of an expert witness is to help the court or tribunal on specialist or technical matters that are within the witness’s expertise and is present to express an opinion on technical matters. Courts find the evidence of specialists extremely important and equally, considerable weight is placed on them in employment tribunal and civil case scenarios, although an expert cannot usurp the ultimate fact finding role of the court or tribunal. An expert witness is normally able to consider all the evidence available, including prosecution or defence statements and reports, before forming and providing an opinion to the court or panel. Experts are nevertheless obliged to provide testimony and opinions about issues that are solely within their professional competence and to remain objective. The facts or assumptions on which their opinion is based must be clearly stated.

Giving evidence in UK internal proceedings or an employment tribunal

Not all legal forums are the same. The composition, procedures and rules of a criminal court, for example, are different to those of a professional regulatory body or an employment tribunal. Professional regulatory panels often consist of three people, one of whom is legally qualified and the others may be drawn from the profession. In an employment tribunal there will often be an employment judge and the other two members are non-legally qualified lay members, one from an employer focused background and one from a trade union or employee related background. Employment cases are sometimes heard by an employment judge sitting alone.

Tribunals and panels are often less formal than criminal court, e.g. there are no wigs or gowns worn and, in most cases, evidence will be given whilst seated at a witness table. As in criminal courts, you will only be permitted to refer to original notes after first seeking the permission of the panel or tribunal.

Again, after you have given your evidence, there is also the opportunity for cross-examination. The amount of time that you will be required to give evidence or be cross-examined may vary and can result in you sitting in tribunal sessions that cross over break periods. It is imperative that during these breaks you do not discuss the case or your evidence with any other party as the oath or affirmation taken at the start of the session still applies until you are dismissed as a witness.

Outside the UK, in many jurisdictions the rules of evidence vary and as such investigators should acquaint themselves with what the protocols are in the jurisdictions in which they are required to operate.

As a general rule, statements of facts are exactly that, facts. As such, regardless of the jurisdiction in which the investigator operates, and the form evidence giving may take, the fundamentals for investigators remain the same.


The best way to learn about giving evidence is to observe courts and tribunals and other legal forums in action. Legal proceedings are normally open to the public which allows the general decorum of the institution, physical lay-out and practical procedures to be observed. The often daunting and esoteric language and practices of courts and other adjudicating bodies become less intimidating the more familiar we are with them.

During such visits you may even see officials and representatives appearing in your case who are acting in other unrelated matters. The practices of an adversarial style legal process become apparent through direct observation and provide the investigator with a better understanding of the role and function of various officials and legal representatives. The value of watching and listening to real proceedings cannot therefore be underestimated. Similarly, the more experienced we ourselves become in giving evidence, the more confident we feel in providing it.

Corporate investigators working for global corporations frequently have the experience of giving evidence in many different types of proceedings in many different jurisdictions. Sharing this experience, but not the case details, with colleagues within the corporate investigation community only benefits our understanding of what giving evidence means, to improve our knowledge in this important area.

Legally reviewed by Tamlyn Edmonds (Edmonds Marshall McMahon).

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