Presumptions of mere law, as shown, are such as are made by the court. There are instances of pveSwnp1aon made by net of parlament, that is, the legislature has declared that a certain fact or facts, when proved, shall be conclusive proof of another improved fact which is not a necessary,and, it may be, is often not a highly probable inference from the proved fact. A statute of 21 James I . , c. 27 (now repealed), made proof of the concealment of the death of a bastard child by the mother conclusive evidence of her having murdered it, unless she could prove that it was born dead. And sometimes an act of parliament declares that a certain presumption shall not be allowed or made. (2 and 3 Wm. IV., c. 71, s. G.) A presumption of mere law is sometimes called an intendment of law.
Presumptions of law and fact arc artificial presumptions, recognised and warranted by the law as the proper inferences to be made by juries under particular 'circumstances. In other words, these are facts which the law, that is, the court, will allow a jury to presume from other facts proved by direct evidence. When the presumed fact is declared by the jury to be a real fact, or is implicitly contained in their verdict, the legal effect is the same. It is said that the iuference (made by the jury) is never conclusive, which appears to mean that there are presumptions which are not necessary, and sometimes may not be highly probable, but they are still such as a jury may make (at least under the direction and advice of the court), and their verdict will be good. Thus a jury is required, or at least advised by a court to infer a grant of an incorporeal hereditament after an adverse enjoyment for the space of twenty years. The presumption of right in such cases is not however conclusive; in other words, it is not an inference of mere law to be made by the courts, yet it is an inference which the courts advise juries to make whenever the pre sumption stands unrebutted by contrary evidence. Such evidence
in theory is mere presumptive evidence; in practice and effect it is a bar.
The third class, the [natural presumptions of mere fact, are wholly independent of any artificial legal relations and connections, and differ from presumptions of mere law in this essential respect, that those depend upon or rather are a branch of the particular system of jurisprudence to which they belong ; but mere natural presumptions are derived wholly by weans of the common experience of mankind from the course of nature and the ordinary habits of society. This class of presumptions properly belongs to a jury, and yet the courts will sometimes make presumptions of this kind without the aid of a jury. These presumptions then are such as a jury may make without the advice or direction of the court, and it seems therefore to be a general rule, that whenever there is evidence on which a jury have founded a presumption according to the justice of the aim, the court+, will not grant a new trial.
Presumption then is either a positive rule by which a certain con clusion is declared by statute, or by the judges, or by the jury under the direction and advice of • the judges, to follow from certain other proved facts; or it is a conclusion from certain other proved facts which a judge or a jury may make if they find the mbative force of the proved facts auflicieut to induce them to make the inference called a natural presumption, or presumptiou of mere fact. Presump tions therefore are incident to every head of law iu which proof is required ; and the presumptions which aro positive rules of law are part of the law of the things to which they relate.
The term " pneaumptio " occurs occasionally in the Digest,' and in the sense of an inference from a fact.proved or admitted. (' Dig.', 22, tit. 3. a. 25.) (Bentham, Rationale of Judicial Evidence ; Starkie, On Evidence ; Phillips, On Eridence.)