Jury Act 1995

The judge before which a civil or criminal trial is to be held may direct that not more than 3 persons be chosen and sworn as reserve jurors.

Reserve jurors—

are to be selected in the same way as ordinary jurors; and

are liable to be challenged and discharged in the same way as ordinary jurors; and

must take the same oath as ordinary jurors; and

are otherwise subject to the same arrangements as other jurors during the trial.

If a juror dies or is discharged after a trial starts but before the jury retires to consider its verdict, and a reserve juror is available, the reserve juror must take the vacant place on the jury.

If 2 or more reserve jurors are available, the juror to take the place on the jury must be decided by lot or in another way decided by the judge.

When a jury retires to consider its verdict, a reserve juror who has not been called on to take a place on the jury must be discharged from further attendance at the trial.

The death or discharge of a reserve juror before the juror has been called on to take a vacant place on the jury does not affect the validity of the trial.