Competent Witness

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Definition: Competent Witness

Competent Witness

Quick Summary of Competent Witness

A competent witness is one who has the sufficient mental capacity to perceive, remember, and narrate the incident he or she has observed. A competent witness must also be able to understand and appreciate the nature and obligation of an oath. For example, a child who is unable to understand the meaning of an oath because of his or her young age is not a competent witness. In statutes relating to the execution of wills, a competent witness is a person who has attested to the will by subscribing his or her name, and at the time he or she attested, could legally testify to the will in court. Persons legally disqualified from testifying because of mental incapacity, personal interest, or conviction of a crime are not competent witnesses.

A witness is generally presumed by the court to be competent.

Video Guide For Competent Witness

Full Definition of Competent Witness

In the law of evidence, a person is ‘competent’ if he or she is legally permitted to give evidence in a court hearing. If a person is competent but unwilling to give evidence, then the question of compellability arises (see compellable witness). However, a non-competent witness is never compellable.

The rules on competence (and compellability) are different in civil and criminal proceedings. In both cases, the basic principle is that a person is competent, but there are exceptions (particularly for the defendant, his or her spouse, children, and people of limited intellect), and those exceptions are different in criminal and civil proceedings.

Civil Hearings

By virtue of the Evidence Act (1851) and the Evidence Amendment Act (1853), any adult of full intellectual capacity is a competent witness for any party. The following sections describe the situation concerning the parties and their spouses, children, and people of limited intellectual capacity.

Civil Hearings: Competence Of Parties And Their Spouses

There are no specific limitations on the competence of the parties and their spouses. Consequently, they are deemed to be competent at all stages in civil hearings.

Civil Hearings: Competence Of Children

There are no specific statutory rules above the competence of children, so the common law test defined in R v Hayes (1976) applies (although this was a criminal case). To be able to give sworn evidence, the child must understand the solemnity of the occasion and the duty, to tell the truth.

However, under s.96 of the children act (1989), even if the Hayes test would result in the child not being able to give sworn evidence, he or she may still be competent to give unsworn evidence:

The child’s evidence may be heard by the court if, in its opinion—

  • (a) he understands that it is his duty to speak the truth; and
  • (b) he has sufficient understanding to justify his evidence being heard.

Civil hearings: competence of persons of limited intellectual capacity

The rules appear to be the same as for children: since there is no express provision to the contrary, the situation will be governed by the Hayes test.

Criminal Trials

The general principle is set out in the youth justice and criminal evidence act (1999):

53(1) At every stage in criminal proceedings all persons are (whatever their age) competent to give evidence.

There are, however, exceptions (see below).

According to s.54 of the 1999 Act, it is for the party who wishes to call a witness to satisfy the court, on a balance of probabilities, that the witness is competent. The court must take into account any ‘special measures’ that may be implemented to protect the witness (see special measures for witnesses).

Criminal Trials: Competence Of The Defendant

By s.54(4) of the YJCEA 1999:

A person charged in criminal proceedings is not competent to give evidence in the proceedings for the prosecution (whether he is the only person, or is one of two or more persons, charged in the proceedings)

This means that the defendant in a criminal trial cannot be called by the prosecution to give evidence against his co-defendants. This measure is intended to protect the defendant’s PrivilegeAgainstSelfIncrimination and right to silence — the ‘right to silence’ would effectively be abolished in multiple-defendant cases if the prosecution could call defendants to give evidence against each other.


(5) In subsection (4) the reference to a person charged in criminal proceedings does not include a person who is not, or is no longer, liable to be convicted of any offence in the proceedings (whether as a result of pleading guilty or for any other reason).

So a person who has pleaded guilty, or had his proceedings discontinued, can be called by the prosecution.

Criminal Trials: Competence Of Defendant’s Spouse

The defendant’s spouse is competent to give evidence for or against the defendant. However, such a person is unlikely to be compellable. See PACE S.80(2A) and (3).

Criminal trials: competence of people of limited intellectual capacity

By s.53(3) of the YJCEA 1999:

‘A person is not competent to give evidence in criminal proceedings if it appears to the court that he is not a person who is able to-

  • (a) understand questions put to him as a witness, and
  • (b) give answers to them which can be understood.

In general, a person who passes the test of s.53(3) is likely to be able to give sworn evidence under s.55.

Criminal Trials: Competence Of Children

The position regarding children is also governed by s.53(3), that is, the child must be able to understand questions and given intelligible replies. However, by s.55, a child under 14 cannot give sworn evidence. A child over that age can only give sworn evidence if he or she has a sufficient appreciation of the solemnity of the occasion and of the particular responsibility, to tell the truth

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January 26, 2022
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Competent Witness. Payroll & Accounting Heaven Ltd. (accessed: January 26, 2022).
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Definition Sources

Definitions for Competent Witness are sourced/syndicated and enhanced from:

  • A Dictionary of Economics (Oxford Quick Reference)
  • Oxford Dictionary Of Accounting
  • Oxford Dictionary Of Business & Management

This glossary post was last updated: 5th January, 2022 | 618 Views.