As a general rule, subject to the sufficiency of evidence and the public interest tests, accomplices should be prosecuted.
Accomplices are not competent witnesses for the prosecution where charged in the same proceedings. However, they may become competent witnesses if dealt with in accordance with the procedures set out below.
An accomplice must be capable in law of committing the offence, e.g. a child under 10 years old can never be classed as an accomplice.
There is no formal legal definition of the term “accomplice”. But the House of Lords has recognised the following as being accomplices:
- a person who takes part in the offence or who aids, abets, counsels or procures its commission;
- a handler at the trial of the actual thief;
- parties to crimes, identical in type to the offence charged, evidence of which has been admitted as proving system and intent and negativing accident (Davies v DPP  AC 378).
Where the evidence of an accomplice is to be used, there is no requirement in law for the judge to give the jury a warning about it. However, the judge has discretion to give a direction where he or she thinks it is advisable to do so.
There may be occasions when it may be appropriate not to bring proceedings against an accomplice even where there is sufficient evidence. For example, the offence might be serious but the involvement of the accomplice may be minor.
There may also be circumstances where it is in the public interest to use an accomplice as a prosecution witness rather than to prosecute him or her. Where this is contemplated, sections 71 to 74 of the Serious Organised Crime and Police must be considered. This legislative framework provides safeguards for the accomplice/assisting offender and the party calling him or her.
Calling an Accomplice as a Prosecution Witness
The evidence of an accomplice may be useful in the following situations:
- to corroborate other witnesses on minor or peripheral issues;
- to provide direct evidence on a point in respect of which the other available evidence is circumstantial;
- to corroborate other evidence which in law requires corroboration or where a corroboration warning would be given;
- where the absence of a witness may cause comment.
Before an accomplice can give evidence for the prosecution, he or she must have never been charged in the proceedings or, if charged, must have;
- pleaded guilty;
- have been acquitted;
- had the case against him/her discontinued.
An accomplice should normally make a witness statement before giving evidence. It should not be signed, if he or she is also being prosecuted, until a guilty plea has been entered. However, a draft may be prepared beforehand.
There is no rule that an accomplice should be sentenced before he or she gives evidence for the prosecution. It is a matter for the trial judge’s discretion.
An accomplice who is called to give evidence who has not previously been required to plead guilty to his or her own part in the offence(s) may incriminate himself or herself in the course of their testimony. Where this happens and either (a) he or she has been treated by the prosecution as a witness and told he/she will not be prosecuted, or (b) he/she has been party to a written agreement under section 72 SOCPA (restricted use undertaking), this fact should be drawn to the attention of the court. The court can be told that the witness will not be prosecuted on the strength of truthful evidence that he or she gives during the trial.