The right to silence is a fundamental principle of Canadian criminal law rooted in section 7 of the Charter (the right to life, liberty, and security of the person) and the common law principle against self-incrimination. An accused person has no obligation to speak to the police, to answer questions, or to provide a statement — at any stage of the investigation or prosecution.
The right to silence means that the Crown cannot use the accused's silence as evidence of guilt. If the accused chooses not to testify at trial, the judge or jury cannot draw an adverse inference from that decision. The Supreme Court of Canada has confirmed that the right to silence is a principle of fundamental justice and that state agents cannot use trickery that effectively eliminates the accused's free choice to speak.
In practice, exercising the right to silence is one of the most important things an accused person can do. Statements made to police are frequently the strongest evidence the Crown has — and once a statement is made, it is extremely difficult to have it excluded. Defence lawyers consistently advise clients to exercise their right to silence and to speak only with their lawyer before making any decisions about cooperating with the police.