The oath (q.v.) to "speak the truth, the whole truth, and nothing but the truth," is administered to witnesses in England on the New Testament; in Scotland, holding up the right hand. Quakers and all conscientious persons, of whatever religious denomi nation, who object to the use of an oath, as formerly observed, make a solemn affirma tion (q.v.); and persons who are foreigners are sworn, or otherwise bound over to speak the truth, by such forms as are conceived to be appropriate to their respective creeds. The test of the amount of religious belief which will suffice to render a witness admis sible, has been generally considered to be a belief in future rewards and punishments; but there is no decision which fixes the point, and in England, belief in a God, and that divine punishment will be the certain consequence of perjury here or hereafter, is enough. To obviate captious objections, the sacredness of oaths was secured by 1 and 2 Viet. c. 105, which provides that all persons shall be bound by the oath administered in the form and with such ceremonies as such persons shall declare to be binding.
It is a general rule of the law of evidence, that a witness is not bound to criminate himself, and he may consequently decline to answer any question that tends to expose him to punishment as a criminal, or to penal liability, or to forfeiture of any kind. If the effect of the question be merely to establish that lie owes a debt, or is otherwise subject to a civil suit, the exception will not hold, and he will be bound to answer it (46 Geo. III. c. 37). The rule in England is, that a counsel, attorney, or solicitor is not bound, or even entitled, to divulge the secrets of the cause with which he has been intrusted; and the recent Shottish act 15 and 16 Viet. c. 27, s. 1, preserves the same excep tion with reference to agents who shall at the time when so adduced be acting in that capacity. Neither‘can official persons be called upon to disclose matters of state, the
publication of which might be prejudicial to the community. All other professional persons, however—lawyers not engaged in the cause, physicians, surgeons, and divines, must divulge all secrets relevant to the issue with which they have become acquainted, even in the strictest professional confidence. See CONFESSIONAL. Neither will a ser vant nor private friend be allowed to withhold a relevant act, though of the most deli cate nature.
One witness in England is sufficient in law, unless in the case of treason, if juries believe him, and in long chains of evidence it is often impossible that more than one witness should be adduced to make out some of the links of it. In general, however, there will be some fact or circumstance which will act as a supplementary adminicle, if the testimony be reliable; and it is this fact which has rendered the practical effect of the opposite rule, which demands two witnesses, in Scotland, not very different. The want of a second witness is usually supplied by a witness to circumstances which are corroborative of the evidence of the first; and where the one witness is not so corrobo rated in England, lie will rarely be believed. It is a rule that none but the best evidence shall be adduced, which means that secondary shall not be substituted for primary evi dence where the latter is accessible; a rule founded on the presumption that such a sub stitution is probably prompted by a sinister motive. This rule applies to as well as oral testimony, and excludes copies of documents, just as it excludes the " hearsay" of witnesses. See OATH, JURY, WITNESS, DEED, TESTING, etc. The best works on evidence in English are Taylor (English), Greenleaf (American), and Dick son (Scotch).