Identify the witness: competence, credibility and oath

Competence: can this person give evidence? Under Youth Justice and Criminal Evidence Act 1999 (YJCEA), s 53, all persons, whatever their age, are competent at every stage of criminal proceedings, subject to its exceptions. The communication exception applies where the person cannot understand questions put as a witness or cannot give answers that can be understood. Both abilities are needed. The separate prosecution-witness exclusion for a person still charged is considered in the next section. Witness competenceGlossary termWitness competence is therefore a legal capacity to communicate evidence, not a certificate of accuracy.

Assess the witness with appropriate questions and support. A young child need not understand an adult's complex vocabulary. A person with a learning disability need not answer an abstract or compound question designed without regard to that disability. The issue is whether understandable questions can produce understandable answers with the support that the court has made, or proposes to make, available. Age, diagnosis, distress, imperfect memory and inconsistency are not themselves statutory grounds of incompetence. Equally, sympathy cannot replace the two required abilities. YJCEA ss 53–54 govern the decision.

Who decides, and how? The judge, District Judge or magistrates decide competence, not the jury. Under s 54, where the issue is raised by a party or the court, the party calling the witness must establish competence on the balance of probabilities: that it is more likely than not that the statutory test is met. The issue is determined without the jury. Expert evidence may assist. If it is necessary to question the witness, the court conducts that questioning in the parties' presence. The assessment assumes the benefit of any relevant special-measures direction already made or proposed. It must not become a rehearsal of the witness's entire account.

Competence, credibility and reliability do different work. A competent witness can lie, honestly misidentify someone, forget detail or contradict another witness. Credibility concerns whether an account should be believed; reliability concerns its accuracy. A truthful witness can be mistaken. Those matters ordinarily belong to evaluation of admitted evidence, not an attempt to exclude the witness by confusing disputed truth with inability to communicate. A competence ruling also does not make every subject on which the witness wishes to speak admissible. YJCEA ss 53–54; CrimPR rr 24.4 and 25.11.

Oath or affirmation: a separate decision. An oath solemnly undertakes to tell the truth. An affirmation is the legally equivalent non-religious undertaking; it is not the same as receiving unsworn evidence. Under YJCEA s 55, a witness under 14 cannot be sworn. A witness aged 14 or over may be sworn only with sufficient appreciation of the solemnity of the occasion and the particular responsibility to tell the truth. Religious belief is not the statutory competence test. Oaths Act 1978, s 5, provides for affirmation by a person who objects to taking an oath.

The presumption and its rebuttal matter. For a witness aged at least 14 who can give intelligible testimony, s 55(3) presumes the required appreciation unless evidence tending to show the contrary is produced. If contrary evidence is produced, the party seeking sworn evidence must satisfy the court, on the balance of probabilities, of the age requirement and the required appreciation. The court determines the issue without the jury and can use expert evidence or its own questioning in the parties' presence. Do not impose an additional examination in theology or a demand for sophisticated definitions. YJCEA s 55(2)–(8).

Unsworn does not mean unusable. A competent witness who cannot lawfully be sworn must give unsworn evidenceGlossary termUnsworn evidence under s 56. The evidence is received and evaluated; the absence of an oath is not a reason to treat it as no evidence. For a child under 14, explaining the need to tell the truth does not remove the statutory prohibition on swearing the child. For an older witness, inability to appreciate the oath does not necessarily establish inability to understand questions and communicate answers.