Presumptions of mere law, as shown, are such as are made by the court. There are instances of presumptions made by Act of Parliament, that is, the legislature has declared that a certain fact or facts, when proved, shall be conclusive proof of another unproved 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 A statute of 21 James I. c. 27 (now repealed), made proof of the con cealment of the death of a bastard child by the mother conclusive evidence of her having murdered it, unless she could prove that it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. Sometimes an Act of Parliament declares that a cer tain presumption shall not be allowed or made. (2 & 3 Wm. IV. c. 71, s. 6.) A presumption of mere law is sometimes called an intendment of law.
Presumptions of law and fact are artificial presumptions which are recog nised and warranted by the law as the proper inferences to be made by juries under particular circumstances." (Star kie, p. 1243.) 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 declared in their verdict, the legal effect is the same as if it were presumed by the judge. Indeed it is said "that the inference (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 pro bable, 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 unanswered." (Starkie, p. 1294.) On this subject it is said in another passage (p. 1214), "the presump tion of right in such cases is not con clusive; 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 presumption stands unrebutted by contrary evidence. Such evidence in theory is mere presumptive evidence ; in practice and effect it is a bar." The third class contains " the natural presumptions of mere fact." " They 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 means of the common expe rience of mankind from the course of nature and the ordinary habits of society." (Starkie, p. 1245.) This class of pre sumptions properly belongs to a jury, and yet the courts will sometimes make pre sumptions of this kind without the aid of a jury. These presumptions then are such as a jury may make without the ad vice or direction of the court, and " it seems to be a general rule that whenever there is evidence on which a jury have founded a presumption according to the justice of the case, the courts will not grant a new trial." (Starkie, p. 1247.) Though this division of presumptions is far from being characterised by precision, it cannot be denied that it is a kind of index to the practice of the courts as to presumptions. The division is founded
—first, on the fact that certain presump tions, which are by no means necessary consequences from the facts proved, are admitted by the judges either as con clusive or as valid, till they are dis proved; these presumptions are some times made by the court, but when it is necessary the court will permit or advise the Jury to make them iu order to arrive at a conclusion as to the fact in question: and, secondly, it is founded on the different functions of the judge and the jury, the former declaring the law, and the latter finding the facts, when their assistance for that purpose is neces sary.
The presumptions of mere law, whether made by the court or by the Mary under its direction, are really artificial rules of proof which have been established by Judicial decisions, or which in any new case the court upon due consideration will make, and if necessary will direct the jury accordingly.
In those courts where there is no jury, one ground of the classification made by Starkie does not exist, and the ,fudge makes his presumptions either in confor mity to the technical rules of his court in cases to which they apply, or he makes his presumptions in cases where there are no technical rules, just as a jury does or any indifferent persons do upon facts sub mitted to them for their consideration.
Presumption then is either a positive rule by which a certain conclusion is declared by statute, or by the judges, or by thejury under the direction and advice of the judges, to follow from cer tain other proved facts ; or it is a con clusion from certain other proved facts which a judge or a jury may make if they find the probative force of the proved facts sufficient to induce them to make the inference called by Starkie a natural pre sumption, or presumption of mere fact. Presumptions therefore are incident to every head of law in which proof is required ; and the presumptions which are positive rules of law are part of the law of the things to which they relate. The subject of Presumptions is an impor tant part of the law of Evidence, and it requires a better discussion than it has yet received.
The term " pnesumptio" occurs occa sionally in the Digest,' and in the sense of an inference from a fact proved or ad mitted. (Dig., 22, tit. 3, s. 25.) The general rule as to proof is, that he who affirms must prove what he affirms, " There are, however, facts which are to be presumed until the contrary is proved, priesnmptiones ; he who maintains such a fact is accordingly relieved from the proof of it : the burden of proof in reference to it is transferred to the opposing party, who maintains the non-existence of the fact; as for example, the continuation of a right which has once begun to exist is presumed, and consequently he who main tains that it has ceased must prove that : he who affirms that he has a right, is only required to prove its acquisition, and not, what is contained in his affirmation, that he still has it." (Puchta, Cirrus, &c., ii. 183.) (Bentham, Rationale of Judicial Evi dence; Starkie, On Evidence ; Phillips, On Evidence.)