BEING A WITNESS
The trial may be many months or even years after you have witnessed the events in question.
If the police or defence lawyer have not taken a formal statement from you, you should write down the event as soon as possible while the facts are fresh in your mind. This material can be used by you later to refresh your memory. If you are a defence witness, and you have given a statement to the police, you should obtain a copy in advance of the trial to refresh your memory.
It is very important that you are completely truthful in your testimony. Prior to testifying, you will be administered the oath and false statements can result in charges of perjury.
Above all, maintain your composure. A frequently used technique of a cross examiner is to attempt to get you angry or frustrated in the hope that you will not be able to recall matters clearly or that your thought processes will become confused. Even if the cross examiner raises his or her voice, you should maintain your composure.
When testifying, take your time and listen carefully to the question being asked. If you do not understand a question, simply say, "I am sorry, but I did not understand the question".
If you did not fully hear a question, say, "I'm sorry I did not hear all that, could you repeat the question please?"
As a witness, you are required to answer the question asked. Your answer should be brief but complete.
Never answer a question with a question. For example, if you're asked a question about something that may or may not have happened, do not answer with, "Well, it must have happened". That is an argument or a conclusion, at best, it is not an answer as to the facts within your knowledge.
Other than for points of clarification, it is not permissible for a witness to ask the interrogator questions.
If you are witness for the defense, you must have confidence in the defence lawyer to object if the question asked by the prosecutor is inappropriate. If the defense lawyer does not object, your best choice is usually to answer the question.