Witnesses
Competence and Compellability
Generally, any person is competent to give evidence provided he has the ability to give an intelligible account of the matters concerned. Historically, the test of competence was whether the witness was in a position to understand the nature and consequences of the oath. A challenge may be made to the competence of children and persons suffering from mental disorder to the give evidence.
The parties to civil litigation decide who they should call as a witness. Generally, this is not a matter for the Court. A witness may be compelled to testify on behalf of any party to the litigation. If he does not attend voluntarily, he may be required to attend by subpoena or a witness summons. He can be compelled by the court to attend and to answer questions properly put. Failure to answer would constitute contempt of court.
There are a limited number of witnesses who may not be compelled. However, they may waive this right and they are then treated as compellable.
In criminal cases, witnesses may be compelled to testify by witness summons. The court may make a witness order requiring attendance at trial of persons whose statement has been served on the accused or whose deposition has been taken.
A witness may be summoned for the purpose of producing documents in civil or criminal cases. There is a special type of subpoena in civil cases, which requires the witness to attend with documents.
Witnesses are presumed to be competent. However, if a witness is challenged, the onus is on the person calling him, to prove his competence. If the competence of a witness is challenged in a jury trial, the matter is heard in the absence of the jury. Doctors, psychologists and psychiatrists may be called to give evidence as to competence
Compelling Attendance
A party may call any person who can give relevant evidence, to be a witness. A witness may be procured to attend a trial by a subpoena. The person served a subpoena shall be tendered their reasonable expenses for attending. This may be little more than the cost of attendance at court. The court may on application grant them a greater level of expenses and losses incurred by them.
A subpoena is applied for by filing an administrative application to the High Court central office. Generally, a court order is not required. Court orders are required in relation to certain cases, including in cases where documents are in the custody of the State. A subpoena can be issued which requires a person to attend with documents under this control, relevant to the matters in dispute.
A subpoena must be served on the prospective witness within 12 weeks of issue. There appears to be power to apply to set aside a subpoena, where it has no basis. A failure to comply with a subpoena is contempt of court. The person subpoenaed may be attached and committed for wilful disobedience.
A person summoned must give evidence on oath or affirmation. Failure to give evidence or giving untruthful evidence constitutes contempt of court and the crime of perjury.
Oaths and Affirmation
Before giving evidence, a witness swears an oath on the New Testament Bible or the Old Testament, if of the Jewish faith. If the witness is not a Christian or Jewish the oath may be administrated in any manner lawful under the Oaths Act 1909. Alternatively, a witness may give a solemn affirmation. Evidence by affirmation has the same effect as a religious oath and carries the same liability for perjury.
A witness’s evidence not given under oath is invalid. The fact that the person swearing the oath has no religious belief and does not believe in it, does not invalidate the proceeding. The courts may allow non-Christian religious oaths, where they are satisfied that it is binding on the conscience of the witness.
It is an offence to give false evidence under oath or to make a false affirmation. It also constitutes contempt in the face of the Court and may be dealt with as such, if it becomes evident during the proceedings.
Children and Mentally Incapable Persons
Children are generally both compellable and competent to give evidence. Formerly, children’s evidence was treated with circumspection and suspicion. In 1992, the former rule, which required corroboration of a child’s evidence, was repealed. The Criminal Evidence Act allows un-sworn evidence to be given by children under 14. In civil proceedings, a similar rule applies under Section 28 of the Children Act 1997.
The child must be able to give an intelligent account of the matters concerned. It is a question for the judge or jury, to decide what weight is to be attached to the evidence. Similar provisions apply to a person suffering a mental disability.
The hearsay evidence rule is relaxed in child welfare proceedings. Prior statements made by a  child may be admitted, where he has been judged unfit to testify.
The Court may enquire into the competence of a person suffering from a mental disability to give evidence. The above provisions in relation to unsworn evidence of children apply to persons with mental disability. There are similar provisions in relation to evidence by television link.
Hostile Witness
A hostile witness is one, who is called by a party who concludes that he is unwilling to tell the truth. In the normal course, a witness cannot be cross-examined and asked leading questions, by or on behalf of the party who has called him. However, where a witness appears to have reversed his position, the party who has called him. may apply to the judge to have him treated as a hostile witness.
If the judge permits the witness to be treated as a hostile witness, leading questions may be asked and he may be cross-examined. He may, for example, be shown to have made prior inconsistent statements. Ultimately, a witness may be guilty of contempt of court,  if he refuses to co-operate with the court. The judge assesses whether a witness should be treated as hostile. In a jury case, this is done in the absence of the jury.
A witness is not hostile in the legal sense, merely because his evidence does not turn out as favourable as hoped to the party who has called him. There must be something to that show an intention not to tell the truth,
Where a witness is accepted as hostile, earlier statements made by him may be used to discredit the witness.  The earlier statement is not evidence in itself,  as this would constitute hearsay. The witness may be asked whether he has made contradictory statements. The contradictory statements may then proved and admitted if they are denied. They are evidence of lack of credibility.
Notes and Statements
Generally, a witness must not bring or rely on notes while giving evidence. However, it is recognised that certain witnesses, such as members of An Garda Siochana, Doctors and other experts may not remember the details of each case without notes, where they deal routinely with many similar cases, particularly where there is a substantial gap before the trial.
Permission is required from the judge to permit a witness to consult notes. It should be vouched that the witness made the notes when the information was recent and fresh in his mind. The notes must be made by the witness or by someone under his supervision. The notes must have been made contemporaneous with, or at least at the first practical opportunity after the relevant event. The rules do not apply to refreshing memory before the trial.
In a criminal case, the Prosecution must notify the defence, if their witnesses have been given access to their statements prior to trial. The witness must give evidence in such cases from his recollection, as refreshed by his notes, and not from the notes themselves
If the witness is able to show that the court that reference to a non-contemporaneous note is required to refresh his memory of a past event, the witness may be permitted either before or during the trial, to reread that note. If it is not contemporaneous, he may not consult it while giving his evidence. The notes themselves are not admissible as evidence.
The witness may be cross-examined on the parts of his notes which become or are the basis of his evidence. This is limited to passages referred to.  In a jury case, the jury may be given copies of the notes on the issue of credibility would not as proof in itself.
Prior Consistent Statements
A person is not allowed to give evidence of his prior consistent statement, for the purpose of bolstering his evidence. A witness may not give evidence of a statement made prior to the trial by another party/witness, which is consistent with his evidence. The purpose is to prevent the manufacture of contrived consistent evidence by repetition of self-serving statements.
There are exceptions to above principle. Whether the statement was made contemporaneous with the material events, it is admitted by way of exception. The same exception applies to the hearsay rule,  on much the same basis. A spontaneous statement, made before there is an opportunity to fabricate, is admissible, on the basis that the spontaneity lends credibility. it is evidence of the matters concerned.
Where the accused is alleged to have recently fabricated his evidence, the prior consistent statement may be used to rebut the challenge. In this latter instance, it is relevant to credibly only.
Collateral Issue
Collateral issues in legal proceedings are those which are not directly relevant to the disputed facts in issue. The classic collateral issue in legal proceedings is the credibility of a witness. In the absence of limitations, a great deal of evidence could be introduced in a trial attacking the credibility of a witness.
In order to prevent the trial from becoming overly complex and becoming deflected onto non-core issues, there are rules which restrict the extent to which contradictory evidence may be introduced on collateral issues. Generally,  the witness’s answers on collateral issues (e.g. reflecting on his credibility) are final, except in limited cases.
The fact that the witness’s answer is final, does not in any way mean that it is conclusive. It simply means that further evidence may not be introduced to contradict the response. There are exceptions to this finality, in relation to certain types of evidence. The judge has the discretion to restrict the extent and duration of the contradictory evidence.
Prior Inconsistent Statement
A witness may be contradicted with evidence of a previous inconsistent statement. The Criminal Procedure Act, 1865 sets out the procedure. If the witness, on cross-examination as to a former statement inconsistent with his evidence, does not distinctly admit it, proof may be given that he did make it. Before such proof can be given, the circumstance of the alleged statement, sufficient to designate the particular occasion must be mentioned to the witness.
The witness must be asked whether or not he has made the prior statement. In the case of a pre-trial statement, the witness must be directed to the relevant passage which contradicts his present statement/evidence. The statement may be received in evidence and the judge may decide to make such use of it for the purposes of the trail, as he sees fit.
The statement may be allowed in evidence, if the witness does not admit to its inconsistency or if it is a confusing account of the same facts It is only allowed as proof of credibility rather than the facts in it.
Challenge Witness Credibility
Evidence may be given of a witness’s general propensity for untruthfulness. Another witness may give an opinion as to the witness’s untruthfulness. Under oath, he may not give details of the circumstances which grant that opinion.
Details may be asked in cross-examination by counsel where the witness’s credibility has been impeached, in attempting to rehabilitate or re-establish his credibility. But in so doing prejudicial information may emerge which might be ruled as a collateral issue may be disclosed.
Where the inconsistent statement relates to an incidental matter, it may be allowed as evidence of his witnesses/accused general lack of truthfulness. The judge should caution the jury, in a jury case, that a lie may be told for a number of innocent reasons and warn them against attaching disproportionate weight to the statement. The direction ought to be given where there is a risk that a jury would attach undue weight to the lie.
Evidence may be given as to the witness’s physical or mental incapacity where is relevant to his ability to give a true account of the circumstances.
Challenging Witness on other Grounds
Evidence is allowed to establish the witnesses’ bias. Where he denies such bias or may be shown to be impartial, or have taken bribes or other incentives not to give honest evidence. Evidence must be shown of attempts to bribe witnesses, coach witnesses or circumstances where he is a criminal accomplice.
Evidence of the previous convictions of a witness may be proved. It need not be otherwise relevant. The crime need not be one that bears on the witness’s honesty.
There was an assumption in common law that a witness with a general propensity for wrongdoing was also capable of lying under oath.
The judge has the discretion to exclude such collateral evidence. This would be more readily exercised in civil cases. The judge may control the extent of cross-examination on convictions having a regard to the interest of justice in a civil case.
Criminal Cases
In a criminal case, the judge will give greater regard to the interests of the accused in a fair trial.
In a criminal case, the prosecution must disclose their evidence and customarily disclose where witnesses have been convicted of offences. The mere examination of a witness as to his character is not necessary. The accused may put his character an issue such that the \”shield\” provided the Criminal Justice Evidence Act 1924 is lost. See the separate section on restrictions on examining accused as to his character.