- The leading authority on how the courts should approach the giving of warnings about the uncorroborated evidence of accomplices or complainants in sexual cases is R v Makanjuola.
- The following principles were laid down in Makanjuola: (i) it is entirely a matter of discretion whether a warning is given at all, and if so, the form of the warning; (ii) in some cases it may be appropriate to warn a jury to exercise caution before acting on the uncorroborated evidence of a witness, but there needs to be an evidential basis for suggesting the witness is unreliable; (iii) a stronger warning may be required where the witness has made false complaints in the past or bears a grudge against the accused, and in such circumstances the judge may suggest that it would be wise to look for ‘supporting material’; (iv) the strength and terms of the warning are for the judge to decide; and (v) the old corroboration rules are entirely abrogated by the Criminal Justice and Public Order Act 1994, s 32 and so there is no requirement to give a corroboration warning in respect of a witness simply on the basis that they are an accomplice or a complainant of a sexual offence. See The Modern Law of Evidence (‘MLE’) 13th ed at pp260-261.
- Where a warning is given to a jury that it is wise to look for supporting material, the jury should warning should also include telling the jury they need to take care about what evidence might constitute ‘supporting material’. For example, if supporting material is possibly lies, they will have to be demonstrated to be lies. Also, a jury may need to be warned that that stress and complaints by a complainant of a sexual offence are not independent evidence. Thus although there has been an understandable desire to get rid of the technicalities of the old corroboration rules, directions to the jury about what constitutes ‘supporting material’ will in some essential respects be the same as the former directions as to what constituted corroboration. See MLE 13th ed at pp261-263.
- It is strongly arguable that as a result of scientific findings by psychologists about ‘childhood amnesia’ (very little if anything can be remembered about the period of childhood before the age of three), a requirement for corroboration should be introduced in respect of witnesses remembering events which occurred in the period before they were three years old. See Keane, The use at trial of scientific findings relating to human memory  Crim LR 19. However, this could involve reintroducing technical rules on what does and does not amount to ‘corroboration’, and the Court of Appeal has strongly deprecated any attempts to re-impose ‘the straightjacket of the old corroboration rules’ (see R v Mankanjuola, MLE 13th ed at p261, para7).