WITNESS, in law, a person who is able from his knowledge or experience to make statements relevant to matters of fact in dispute in a court of justice. The relevancy and probative effect of the statements which he makes belong to the law of evidence (q.v.). In the present article it is only proposed to deal with mat ters concerning the position of the witness himself. In England, in the earlier stages of the common law, the jurors seem to have been the witnesses, for they were originally chosen for their knowledge or presumed knowledge of the facts in dispute, and they could (and can) be challenged and excluded from the jury if related to the parties or otherwise likely to show bias.
Competency.—Modern views as to the persons competent to give evidence are very different from those of Roman law and the systems derived from it. In Roman law the testimony of many persons was not admissible without the application of torture, and a large body of possible witnesses was excluded for reasons which have now ceased to be considered expedient, and witnesses were subject to rules which have long become obsolete. Witnesses must be idonei or duly qualified. Minors, certain heretics, infamous persons (such as women convicted of adultery), and those in terested in the result of the trial were inadmissible. Parents and children could not testify against one another, nor could slaves against their masters, nor those at enmity with the party against whom their evidence was offered. Women and slaves could not act as witnesses to a will. There were also some hard and fast rules as to number. Seven witnesses were necessary for a will, five for a mancipatio or manumission, or to determine the ques tion whether a person were free or a slave. As under the Mosaic law, two witnesses were generally necessary as a minimum to prove any fact. Unius responsio testis omnino non audiatur are the words of a constitution of Constantine. The evidence of a single wit ness was simply semi-plena probatio, to be supplemented in de fault of a second witness, by torture or reference to oath. The canon law followed the Roman law as to competence, but ex tended the disabilities to excommunicated persons and to a layman in a criminal charge against a clerk, unless he were actually the prosecutor. The evidence of a notary was generally equivalent to that of two ordinary witnesses. The evidence of the pope and that of a witness who simply proved baptism or heresy (according to some authorities) are perhaps the only other cases in which canon law dispensed with confirmatory evidence. It is probable that the
incompetence of Jews as witnesses in Spain in the 14th and 15th centuries was based on what is termed "want of religion," i.e., her esy or unwillingness to take the Christian oath on the gospels. But in England until their expulsion they were on the status of slaves (captivi) of the king. A policy similar to that of the Roman law was followed for centuries in England by excluding the testimony of parties or persons interested, of witnesses for a prisoner, and of infamous persons, such as those who had been attainted or had been vanquished in the trial by battle, or had stood in the pillory. All these were said vocem non habere. In the days of trial by bat tie a party could render a witness against him incompetent by chal lenging and defeating him in the judicial combat. Women were generally regarded as wholly or partially incompetent. English law had also certain rules as to the number of witnesses neces sary. Thus under a statute of 1383 (6 Rich. II. St. 2 c, 5) the num ber of compurgators necessary to free an accused person from complicity in the peasant revolt was fixed at three or four. Five was the number necessary under the Liber feudorum for proving ingratitude to the lord.
In the course of the gradual development of the law of evidence, which is in a sense peculiar to the English system, the fetters of the Roman rules as to witnesses were gradually shaken off. In civil cases all disabilities by interest, relationship, sex or crime have been swept away. The witness need not be idoneous in the Roman sense, and objections which in Roman law went to his com petence, in English law go to his credibility. The only general test of competency is now understanding. It excludes lunatics, idiots, dotards and children of tender years ; a person convicted of per jury is said to be competent if convicted at common law, but in competent if convicted under the act of Elizabeth. No trial ever takes place now under this act, and on this point the act seems to have been virtually repealed by Lord Denman's act (1843 ; 6 and 7 Vict. c. 85). The disqualification is not absolute as to luna tics; as to children it is sometimes made to depend on whether they are able to understand the nature of the witness's oath. And in certain cases within the Criminal Law Amendment Act, 1885, and the Prevention of Cruelty to Children Act, 1904, the unsworn evidence of children of tender years is admissible but needs corroboration.