The Right to Remain Silent is a critical legal principle in our Criminal Justice system.
Section 7 of the Charter accords a detained person a pre‑trial right to remain silent, and the scope of that right extends beyond the narrow formulation of the confessions rule. The rules relating to the right to remain silent adopted by our legal system, such as the common law confessions rule and the privilege against self‑incrimination, suggest that the scope of the right in the pre‑trial detention period must be based on the fundamental concept of the suspect’s right to freely choose whether to speak to the authorities or remain silent.
This concept, which is accompanied by a correlative concern with the repute and integrity of the judicial process, is consistent with the right to counsel and the right against self‑incrimination affirmed by the Charter. It is also consistent with the Charter‘s approach to the question of improperly obtained evidence under s. 24(2) and with the underlying philosophy and purpose of the procedural guarantees the Charter enshrines — in particular in s. 7. That section imposes limits on the power of the state over the detained person and seeks to effect a balance between their respective interests.
Under s. 7, the state is not entitled to use its superior power to override the suspect’s will and negate his choice to speak to the authority or to remain silent. The courts, therefore, must adopt an approach to pre-trial interrogation which emphasizes the right of a detained person to make a meaningful choice and which permits the rejection of statements which have been obtained unfairly in circumstances that violate that right of choice.
The test to determine whether the suspect’s choice has been violated is essentially objective. The focus of the inquiry under the Charter will be on the conduct of the authorities vis-à-vis the suspect. Further, since the right to remain silent under s. 7 is not an absolute right but must be qualified by considerations of the state interest and the repute of the judicial system, the Clarkson standard relating to waiver of a Charter right does not apply to the right to silence.
Source: R. v. Hebert, 1990 CanLII 118 (SCC),  2 SCR 151
Do I have to Speak to the Police?:
In general, “no”.
Another of our basic legal principles is the right of every person to refuse to assist the state to prosecute himself. The main illustration of this concept is the well-known right to remain silent (sometimes called the protection against self-incrimination).
An individual who is suspected or accused of committing a crime has the unequivocal right to refuse to say anything to the police and cannot be punished for refusing to do so. Even witnesses are entitled to refuse to speak with the police if they wish.
Witnesses may have a moral duty to assist police investigating an incident, but that is not the same as a legal duty. The right to remain silent is so important that the police are required to tell anyone being arrested that they have that right and if they give up the right to remain silent, anything they say can be used in court.
There are at least a couple of small exceptions to the right to remain silent. One exception is in relation to the identification of a suspect or accused person. Strictly speaking, the right to remain silent includes confirming one’s identity and basic personal information (mainly, date of birth) to the police.
However, in many situations involving relatively minor offences, the police are not permitted to arrest the accused but instead, issue legal documents requiring that individual to come to court to answer the charges and then let the person go on their way. In such cases, if the person does not identify themselves, the police have the power to arrest in order to establish their identity, usually through fingerprinting.
Another example of an exception of the right to remain silent also arises in the area of motor vehicles. Just as the police have the power to require motor vehicles to stop, they also have the power to demand the driver provide them with proof of registration and insurance, and allow them to inspect his personal driver’s license. If the vehicle has been involved in an accident, in most jurisdictions the driver is also required to provide a statement as to what happened. Failure to comply with these duties is a provincial offence. However, this applies only to the driver of a motor vehicle; passengers are fully entitled to remain silent and do not have to identify themselves unless the police have proper legal grounds to ask them to do so.
Source: LawNow Magazine, 2017 CanLIIDocs 298
Police Can Still Ask Questions:
The scope of the right to silence, however, does not go as far as to prohibit police from obtaining confessions in all circumstances. The proposed approach to the s. 7 right to silence retains the objective approach to the confessions rule and would permit the rule to be subject to the following limits.
First, there is nothing that prohibits the police from questioning an accused or a suspect in the absence of counsel after he has retained counsel. Police persuasion, short of denying the suspect the right to choose or of depriving him of an operating mind, does not breach the right to silence.
Second, the right applies only after detention.
Third, the right does not affect voluntary statements made to fellow cell mates. The violation of the suspect’s rights occurs only when the Crown acts to subvert the suspect’s constitutional right to choose not to make a statement to the authorities.
Fourth, a distinction must be made between the use of undercover agents to observe the suspect, and the use of undercover agents to actively elicit information in violation of the suspect’s choice to remain silent.
Finally, even where a violation of the suspect’s right is established, the evidence may, where appropriate, be admitted. Only if the court is satisfied that its reception would be likely to bring the administration of justice into disrepute can the evidence be rejected under s. 24(2) of the Charter. Where the police have acted with due care for the suspect’s rights, it is unlikely that the statements they obtain will be held inadmissible.
Source: R. v. Hebert, 1990 CanLII 118 (SCC),  2 SCR 151
Importance of NOT Speaking to the Police:
Spend a few minutes and watch this video to understand how important and crucial it is to remain silent: