The right to silence is protected under the Charter. The accused may not be compelled as a witness against himself in criminal proceedings, and therefore only voluntary statements made to police are admissible as evidence.
Prior to an accused being informed of their right to legal counsel, any statements they make to police are considered involuntarily compelled and are inadmissible as evidence. After being informed of the right to counsel, the accused may choose to voluntarily answer questions and those statements would be admissible.
As far as pre-trial silence is concerned, a person who is subject to the coercive power of the state has a right to refuse to answer questions; this happens on the person’s arrest, charge or detention. This right to silence has been recognised as a principle of fundamental justice, protected by s 7 of the Charter: see R v Hebert [1990] 2 SCR 151. It is also accepted that the exercise of the right to silence can not be used against the accused at trial: see R v Chambers [1990] 2 SCR 1293.
Although an accused has the right to remain silent and may not be compelled to testify against himself, where an accused freely chooses to take the witness stand and testify, there is no further right to silence and no general restriction on what kinds of questions they may be required to answer.
This may be contrasted with the US right to refuse to answer incriminating questions under the 5th Amendment even while on the witness stand. However section 13 of the Charter of Rights and Freedoms guarantees that a witness may not have any incriminating evidence they gave as testimony used against them in separate proceedings. In effect, a person can be compelled to give involuntary self-incriminating evidence but only where that evidence is to be used against a third party.
In most cases, except for certain sex offences or where the victims are children, spouses can not be compelled to testify against each other. This right does not include lying to persons in authority but the right to refuse to answer any and all questions.