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[1977] 64 Cr App R 194 (CA). The defendant was convicted after the trial judge allowed children aged 11 and 12 to give sworn evidence. On appeal the defendant contended that these children were too young to appreciate the nature of the oath, and their evidence should not have been admitted. However, the Court of Appeal held that the important factors in determining whether a witness should be sworn were whether the witness appreciated the solemnity of the occasion, and understood the importance of telling the truth. Consequently the appeal was dismissed.

The 'Hayes test' for the competence of a child (or a person of limited intellectual capacity) continues to stand, but it is now subject to some limitations.

s.55(2)(b) of the youth justice and criminal evidence act (1999) essentially restates the Hayes test in statutory form, but s.55(2)(a) states that nobody under 14 may give sworn evidence. In civil hearings it appears that the Hayes test still applies, but s.96 of the children act (1989) goes on to set out further limitations on a child's being able to give unsworn evidence.