Rules about giving evidence

Introduction

When you are giving evidence, the lawyers and the judge can object to certain things you say. This is because there are legal rules about what evidence you can give.

The judge can interrupt you and ask you to stop if one of the rules of evidence is being broken.

It is also a criminal offence to give evidence which you know is false. This is known as perjury.

Rules

As a witness, you can only give evidence about facts within your own personal knowledge. You cannot testify about what somebody else saw or heard.

You cannot give evidence about your opinion. Your testimony must be a statement of the facts. It cannot contain any assumptions you have made, or conclusions you have drawn from those facts. The exception to this rule is the expert witness who can give evidence that is their opinion.

You cannot give evidence about what someone else said. This is known as the hearsay rule. For example, you cannot give evidence that your mother told you she saw the accused grab your purse. In that case your mother would need to give evidence in court to say that she saw the accused grab your purse.

You cannot give evidence about previous statements you have made. For example, you cannot give evidence that you told your friend that the accused grabbed your purse. You can only give evidence about the actual incident. However, if you are giving evidence as a victim of rape, you can introduce evidence that you made a complaint after the rape.

Your main duty as a witness is to tell the court the truth. If you knowingly make a false statement under oath, you may have committed the crime of "perjury" and you can be prosecuted.

Right to refuse to answer a question

If you are giving evidence (either during the examination or the cross-examination), and you do not want to answer a question, you must let the judge know that you are not prepared to answer the question and why.

There are very few circumstances where a judge will allow you to refuse to answer a question if it is relevant to the case. The right to refuse is known as a privilege. Privilege applies in the following situations:

  • Privilege against self-incrimination: means that you can refuse to answer questions or hand over documents that may implicate you in criminal proceedings.
  • Legal professional privilege: means a legal advisor and their client cannot be forced to disclose communications between them. If any communication is made in contemplation of litigation (for example, with a court case in mind), then that communication is also privileged.
  • Sacerdotal privilege: means that priests can refuse to answer questions about what was said in the confessional. Similarly, communications with a counsellor can also be privileged.

If you object to answering a question, the judge will decide if you must answer the question. If the judge decides that you cannot rely on a "privilege", then you must answer the question. If you fail to do so, you will be in contempt of court and you can be imprisoned.

Perjury

It is a criminal offence to give evidence which you know is false (perjury). This applies to evidence given while in court or any evidence which is included in an affidavit (a sworn written statement from you) or anything in a statutory declaration.

It is also a criminal offence to force, persuade or induce someone to commit perjury.

A person who commits perjury can be fined up to €100,000 and/or imprisoned for up to 10 years.

Further information

You should get legal advice for more detailed information.

Page edited: 17 August 2021