CHAPTER XXV.

THE INSTRUMENTS OF EVIDENCE.

THE instruments of evidence consist of witnesses and documents.

Witnesses. A witness may be defined to be one who gives evidence under the obligations of an oath.

The testimony given by witnesses is called parol evidence, as contradistinguished from that derived from documents, termed documentary.

This division of the subject of evidence will be discussed under the following heads :

(1) Competency of witnesses, (2) Credibility of witnesses. (3) Examination of witnesses.

COMPETENCY OF WITNESSES.

It is the general rule that all persons are competent to give evidence. To this, however, there are certain exceptions, which being proved, will render witnesses incompetent :

Incompetency how ascertained. Proof of such incompetency is necessary, as it is never presumed.

The ordinary mode of ascertaining whether a witness is competent is by examination on the voire dire before being sworn. Should he appear incompetent from his answers, he is rejected. If his answers are satisfactory, other witnesses may be called to show his incompetency. It sometimes happens that the incompetency of a witness

is not discovered until after he has been sworn and his examination proceeded with a considerable way, or perhaps even brought to a close; under such circumstances the court ought not to consider his evidence in coming to a finding.

Should a ground of incompetency be discovered during the examination of a witness, his examination may be suspended, and he may be put on his voire dire to examine him as to his competency.

Exceptions. The exceptions to the general rule that all persons may give evidence may be arranged under the following heads:

1. Want of religious principle. 2. Want of understanding. 3. Interest. 4. Infamy.

Incompetency from Want of Religious Principle. One of the chief requirements of the law for securing truth in parol evidence is that it be given under the sanction of an oath. But from the nature of an oath, it would have no sanction if a party did not believe in the existence of a Divine Being, and a state of future rewards and punishments. Persons, therefore, who have not such belief are incompetent to testify.

The particu

Nature of Religious Faith required. lar religion of the party does not affect his competency, so long as he professes a religion that can bind his conscience. An infidel may be allowed to testify if he believes in a God who will punish. Some State courts have gone so far as to require only belief in the existence of a God, without reference to a belief in a state of future rewards and punishments; but the true test seems to be belief of a God, and that he will reward and punish us according to our deserts.1 It is not material whether the witness believes the punishment will be inflicted in this world or the next.

1 Greenleaf, Vol. I. § 369, Note 3,

How Proved. Defect of religious principle is never presumed, and the objection to a witness's competency on this ground should be made by the adverse party before he is sworn. Some difference of opinion has existed as to the manner of proving incompetency. The modern practice is not to question the witness himself, but to ask third persons to testify whether he has declared his belief in God, and in a state of future rewards and punishment.

Should the witness set up change of belief, this should be shown in the same way by his declarations to third parties.

Witnesses how Sworn. Witnesses should be sworn in the manner which they deem most binding on their conscience. The ordinary mode, as before pointed out, in court-martial proceedings is as follows: The witness, standing, holds up his bare right hand, and the judge-advocate repeats the prescribed oath. It should be administered in the exact language of the law, and by the person authorized to administer it. The court may ask the witness if he considers the form of administering the oath binding on his conscience, and the proper time for making this inquiry is before he is sworn. But if the witness without making any objection, takes the oath in the usual form, he may be afterwards asked whether he thinks the oath binding on his conscience; but it is unnecessary and irrelevant to ask him if he considers any other form of oath more binding, and, therefore, such question cannot be asked.

If witness, without objecting, is sworn in the usual mode, but, being of different faith, the oath was not in a form affecting his conscience, as if, being a Jew, he was sworn on the Gospels, he is still punishable for perjury, if he swears falsely.'

1 Greenleaf, Vol. I. § 371. Wharton's Crim. Trials, § 2205.

Affirmation.

The statutes of the United States provide that the requirement of an "oath" shall be deemed complied with by making affirmation in judicial form.'

For the violation of the truth in such cases the witness is subject to the punishment of perjury, as if he had been

sworn.

Incompetency from Want of Understanding. Under this head will be considered :

(1st) Children. In former times the age of a child was regarded as the criterion of competency; but now competency is determined by the degree of understanding which a child appears to possess. At the age of fourteen the law presumes every person to have common discretion and understanding until the contrary appears; under that age, competency not being presumed, it is proper to make inquiry as to the degree of understanding, and if the child appears to have sufficient natural intelligence, and to have been so instructed as to comprehend the nature and effect of an oath, he is admitted to testify, whatever his age may be. If the child, being a principal witness, appears not yet sufficiently instructed in the nature of an oath, the court will, in its discretion, put off the trial that this may be done.2

(2d) Idiots and Lunatics. Persons not possessing the full use of their understanding cannot be allowed to testify. An idiot is a person who has been non compos mentis from his birth, and who has never had any lucid intervals. He cannot be received as a witness. A lunatic is a person who has had understanding, but who, by disease, grief, or other accident, has lost the use of his reason. If he has lucid intervals he may be allowed to testify, but he must have been of sound mind at the time the event happened, and also at the time he testifies; and it ought to Greenleaf, Vol. I. § 367.

1 § 1, Revised Statutes.

appear that no serious fit of insanity has intervened. Intoxicated persons are not allowed to testify until sober.

(3d) Deaf and Dumb Persons. Persons deaf and dumb from birth, in contemplation of law, are regarded as idiots. If, however, they are shown by the party adducing them to have sufficient understanding, they may give evidence either by writing, or by signs interpreted to the court.

Incompetency from Interest. The general rule in both criminal and civil suits is that a party interested is not competent.

So far as courts-martial are concerned, the following cases need alone be considered:

(1) Relationship. Husband and wife are, in general, incompetent witnesses for or against each other, on the ground of identity of interest, the great danger of perjury, and the extreme hardship of the case. Where the rela

tion of husband and wife has once existed, even after the relation has ceased, the parties are incompetent to testify for or against each other as to matters which occurred during the continuance of the relation.

The rule applies only to lawful marriages. Where a woman has cohabited with a man as his wife, but is not so in fact, she is a competent witness for or against him.'

Exceptions. There are certain exceptions to this rule, and it should be remembered that where either party is competent for they are competent against.

(a) Collateral Proceedings. In collateral proceedings, not immediately affecting their mutual interests, their evidence is receivable notwithstanding it may tend to criminate, or may contradict the other, or may subject the other to a legal demand. The reason of this is that they could not be admitted as witnesses, nor could their evidence in the first suit be produced against each other if an