Unfit to plead

In the law of England and Wales, fitness to plead is the capacity of a defendant in criminal proceedings to comprehend the course of those proceedings. The concept of fitness to plead also applies in Scots and Irish law. Its United States equivalent is competence to stand.

If the issue of fitness to plead is raised, a judge is able to find a person unfit to plead. This is usually done based on information following a psychiatric evaluation.

In England and Wales the legal test of fitness to plead is based on the ruling of Alderson B. in R v Pritchard. The accused will be unfit to plead if he is unable either:

If the issue is raised by the prosecution, the prosecution must prove beyond reasonable doubt that the defendant is unfit to plead. If the issue is raised by the defence, it need only be proved on the balance of probabilities.

In Scotland the test is based on HMA v Wilson, and has two elements:

The question of unfitness to plead is determined by a judge. The decision should normally be made as soon as it arises, which would ordinarily be before arraignment, but the court may postpone consideration of unfitness until any time before the opening of the defence case. This power might be used to allow the defence to challenge the prosecution case on the basis that there is no case to answer.

If the judge determines that the defendant is unfit to plead, evidence will be heard and the jury will be asked to determine whether he did the act or made the omission charged against him as the offence. This process avoids the detention of innocent persons in hospital merely because they are mentally unfit. It has been held that the reference to the "act or omission" means that the jury should not normally consider whether the defendant had the requisite mens rea.

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Wikipedia