Who can be a witness at a trial depends on two factors, competence and compellability.
The competence of a witness refers to whether a witness is legally permitted to testify and give evidence. The compellability of a witness refers to the power to force a competent witness to testify even if it's against their will.
At common law, all individuals are presumed competent to testify so long as their information is relevant barring certain groups of people. Historically, the common law prevented many types of people from testifying. This included convicts, infants, the insane, marriage, and lack of belief in a higher power. Many of these rules have been overturned by statute, for example, the rule against convicts was removed under by section 12 of the CEA. Their record, however, can be used as character evidence.
The three classes of exceptions that remain today are children, people of low mental capacity, and spouses. In each of these it is up to a challenger to establish the incompetence of the witness.
A witness is presumed to possess both capacity and responsibility. More specifically, to testify, a witness need only be able to # observe,
In order to communicate the witness must be able to understand and respond to questions, and the witness must have the moral responsibility to speak the truth.
The proof of competency or incompetency is on the balance of probabilities. [ 1 ] Where competency is challenged, it must be established by a voir dire before the witness can be sworn. [ 2 ]
A witness who states that they may not tell the truth is still competent to testify. Such issues of truthfulness are factors of credibility for the trier-of-fact. [ 3 ]
A witness who is barred by foreign law to testify is still competent. [ 4 ]
A competent witness is generally a compellable witness. [ 1 ]
But an incompetent witness is generally not compellable.
Section 698 allows the ordering of a subpoena requiring a witness to attend court:
698. (1) Where a person is likely to give material evidence in a proceeding to which this Act applies, a subpoena may be issued in accordance with this Part requiring that person to attend to give evidence.
(2) Where it is made to appear that a person who is likely to give material evidence
(a) will not attend in response to a subpoena if a subpoena is issued, or (b) is evading service of a subpoena,a court, justice or provincial court judge having power to issue a subpoena to require the attendance of that person to give evidence may issue a warrant in Form 17 to cause that person to be arrested and to be brought to give evidence.
(3) Except where paragraph (2)(a) applies, a warrant in Form 17 shall not be issued unless a subpoena has first been issued.
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The key factor is that the issuing party must be able to establish that the witness would likely or probably have material evidence to give. It is not enough that the witness "may have" material evidence. [ 2 ]
Where the subpoena is not valid it may be quashed by a superior court judge. [ 3 ]
A judge has a discretion to excuse an expert witness who is under a valid subpoena. [ 4 ]
Where the matter is before a provincial court judge and the person is within the province, a provincial court judge may order their attendance by issuing a subpoena under s.699(2)(a). However, under s. 699(2)(b), where the witness is out of province, either a provincial court a superior court judge may order the subpoena.
Where the matter is before a superior court judge, only that court may issue a subpoena compelling attendance (s. 699(1)).
Section 705 gives authority of a court to issue a warrant of arrest for a witness who fails to attend on a subpoena.
Warrant when witness does not attend
(a) that the subpoena has been served in accordance with this Part, and (b) that the person is likely to give material evidence, issue or cause to be issued a warrant in Form 17 for the arrest of that person.
705. (1) Where a person who has been served with a subpoena to give evidence in a proceeding does not attend or remain in attendance, the court, judge, justice or provincial court judge before whom that person was required to attend may, if it is establishedWarrant where witness bound by recognizance
(2) Where a person who has been bound by a recognizance to attend to give evidence in any proceeding does not attend or does not remain in attendance, the court, judge, justice or provincial court judge before whom that person was bound to attend may issue or cause to be issued a warrant in Form 17 for the arrest of that person.Warrant effective throughout Canada
(3) A warrant that is issued by a justice or provincial court judge pursuant to subsection (1) or (2) may be executed anywhere in Canada.R.S., 1985, c. C-46, s. 705; R.S., 1985, c. 27 (1st Supp.), s. 203.
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A judge has the inherent authority to order any person present in court to be compelled to testify where:
Similarly, an inmate witness can also be compelled to testify by way of s. 527. [ 1 ]
Where a witness fails to attend, the judge has a discretion to order a witness warrant where he is satisfied that: [ 2 ]
Common law requires all witnesses to take an oath to solemnify the evidence given. The implicit threat of divine intervention does not have the same weight as it did historically. As Justice Dickson stated in R. v. Bannerman, "[t]he object of the law in requiring an oath is to get at the truth relative to the matters in dispute by getting a hold on the conscience of the witness." Thus, there is a second option provided to allow people to opt for taking an affirmation of solemnity. This is provided under section 14 of the Canada Evidence Act (CEA) as well as under most provincial evidence acts [ 1 ] . The form of the ceremony can vary. It can even be as simple as asking "do you know that it is a criminal offence to intentionally give false evidence in a judicial proceeding? Do you solemnly promise to tell the truth in this proceeding?"
The key to a proper oath or affirmation is that the witness understands what they are swearing to. Typically, it is not a problem with the exception when dealing with Children and witnesses of low mental capacity as will be seen later.
Rules surrounding the testimony of children is of particular importance. The reason for this is that children tend to be highly susceptible to influence, their ability to interpret events often affects their testimony, they may not understand the consequences of their actions, and they typically have a higher degree of credibility to a trier of fact.
At common law there is no minimum age for testimony. However, invidividuals of "tender years" (i.e. under fourteen) must be tested to see if they "possessed sufficent intelligence" to be considered competent, and understand the "nature and consequences" of an oath. If they were not able to understand the meaning of the oath they would usually be allowed to give unsworn testimony so long as the evidence they gave could be corroborated.
In regards to the understanding of the oath, Justice Dickson, in R. v. Bannerman stated that "all that is required when one speaks of an understanding of the "consequences" of an oath is that the child appreciates it is assuming a moral obligation." This test remains the common law requirement for an oath and still applies for civil trials in provinces that have not adopted the recent changes seen the CEA.
Section 16(1) of the CEA, was introduced in 1987 had changed much of the rules for children and people of low mental capacity. Much of the common law rules are preserved. The common law presumption of competence is preserved, subject so section 16(1), which states:
16(1) Where a proposed witness is a person under fourteen years of age or a person whose mental capacity is challenged, the court shall, before permitting the person to give evidence, conduct an inquiry to determine
(a) whether the person understands the nature of an oath or a solemn affirmation; and
(b) whether the person is able to communicate the evidence.
If the child passes this test then they will be allowed to testify under section 16(2) of the CEA.
However, in the event that the child does not understand the meaning of the oath they are still able to give an unsworn testimony under section 16(3) on the condition that they promise to tell the truth. There is an additional test that must be applied in order to accept a promise to tell the truth. The individual must understand what it means "to promise" and understand what it means to "tell the truth". The test for the truth is neither exact or demanding. It mostly involves having the child "commit" to telling the truth as they understand it in everyday social conduct. The distinction of this from the test to determine if the child understands the oath is that there is no requirement for the child to understand the solemnity of the court and does not need to understand their duty beyond everyday meaning of it.
For all unsworn testimony, in R. v. Kendal, the Court held that whenever a child gives sworn testimony the judge must warn the jury regarding the dangers of convicting based on a child's testimony. This practice is applied in any event to witnesses who give inconsistent evidence.
In comparasion wit the common law requirement for corroboration, section 16(3) removes this.
The first step lowers the bar set by Marquard and only requires that they are able to communicate. The second step is a substitute for the need to take an oath or affirmation. If the child promises to tell the truth it will be as good as an oath (s.16.1(8)). When challenging the second step, however, the challenger is not allowed to ask about the "nature" or "meaning" of what it means to tell the truth.
The section 4(5) exception preserves the common law rule. [ 3 ] It can be invoked even where the witness spouse is not the victim but their health or liberty is threatened. [ 4 ]
Thus, generally speaking spouse cannot testify on behalf of a co-accused or the crown. In civil trials, provincial evidence acts have removed these presumption, allowing spouses to testify in all circumstances.
The immunity is concern with the state of the relationship at the time of the evidence being given, and not at the time of the incident. [ 5 ]
The protection is only only those in a "valid and subsisting" marriage. [ 6 ] Thus, the spousal exception does not surived the marriage. "Irreconcilably separated" spouses are not protected where there is no marital harmony to preserve. Thus, spouses with "no reasonable prospect of reconciliation" is exempt from spousal immunity. This is determined objectively and on the balance of probabilities. [ 7 ] .
A spouse refers only to legally married spouses. Those who are:
are not subject to the spousal immunity.
A competent spouse for a party is necessarily a compellable witness. [ 9 ]
Even where the witness spouse is competent to testify, this does not necessarily always remove spousal privilege. [ 10 ] However, spousal privilege cannot apply where s. 4(2) is applied. [ 11 ]
An accused person is generally assumed competent and compellable for the defence and not competent for the crown.
A co-accused, charged separately, is a competent and compellable witness for both crown and defence. The only exception is if the only purpose in compelling the co-accused is to incriminate them. [ 1 ] The same goes for suspects, charged or uncharged. [ 2 ]
A co-accused, charged together, is competent but not compellable by the accused. It is the choice of the co-accused to testify.
A lawyer for an opposing party to an ongoing matter may only be called to testify where the calling party has shown a high degree of materiality and necessity. [ 3 ]
A juror is a competent witness. [ 4 ] A juror cannot testify to any evidence concerning the deliberations, emotions, or decisions of any of the jury panel. [ 5 ]