Being a Witness in a Criminal Court Case


Being a witness in a criminal case involves telling what you saw, experienced or heard about a crime. As a witness, you are only allowed to talk about events that you know about personally.

For example, when you are a witness in court, you can't say "I wasn't there, but someone told me that the thief was wearing a grey sweater."

Who can be a witness?

As a general rule, anyone who has relevant information can be a witness. Here are some examples:

  • a victim, to describe what happened
  • people accused of a crime, to speak in their own defence
  • police officers, to explain the facts they noted down at the station
  • eyewitnesses, namely people who saw what happened

You can be called as a witness even if you are under 18. If you are under 14, the judge could verify that you will be able to understand and answer the questions that you are asked.

The only people who can give their opinions as witnesses in court are expert witnesses. The testimony of an expert is used to explain more complex facts. For example, a fingerprint expert can give an opinion about whether the fingerprints taken at the scene of the accident and submitted in evidence are those of the accused.

The Duty to Be a Witness

When you are obliged to be a witness in a court case, obviously you can do so willingly. But generally, you will receive "a summons ", also called a "subpoena".  That document requires you to appear in court on the dates and times indicated.

If you don't show up and give your testimony, the judge can ask the police to arrest you and force you to come to court!

The accused is never obliged to be a witness because the accused has the right to remain silent.

What is involved in being a witness?

Before a witness starts to answer questions, the court clerk will ask a witness who is 14 or over to take an oath or say "I solemnly affirm that the evidence to be given by me shall be the truth, the whole truth and nothing but the truth."  If the witness is under 14, the court clerk simply asks the witness to promise to tell the truth. 

Witnesses have to answer all questions truthfully. Note that anyone over the age of 14 who lies in court commits a crime known as "perjury".

After the oath is given by the clerk, the witness can start giving evidence. This involves these three important steps:

  • Examination: The lawyer who called the witness to give evidence questions the witness first.
  • Cross-examination: Then the lawyer for the other side asks the witness questions. The purpose of cross-examination is to cast doubt on the credibility of the witness. The lawyer can try to show the court that the witness doesn't remember clearly or accurately what happened, that the witness is not impartial or that the witness is not telling the whole truth.
  • Re-examination: If the first lawyer thinks it's necessary, he or she can examine the witness again to clarify, correct or explain what was said during cross-examination.

Important !
This article explains in a general way the law that applies in Quebec. This article is not a legal opinion or legal advice. To find out the specific rules for your situation, consult a lawyer or notary.