In the law of evidence, a presumption of a particular fact can be made without the aid of proof in some situations. The types of presumption include a rebuttable discretionary presumption, a rebuttable mandatory presumption, and an irrebuttable or conclusive presumption. The invocation of a presumption shifts the burden of proof from one party to the opposing party in a court trial. Presumptions are sometimes categorized into two types: presumptions without basic facts, and presumptions with basic facts. In the United States, mandatory presumptions are impermissible in criminal cases, but permissible presumptions are allowed.

The ancient Jewish law code, the Talmud, included reasoning from presumptions (hazakah), propositions taken to be true unless there was reason to believe otherwise, such as "One does not ordinarily pay a debt before term."<ref>J. Franklin, The Science of Conjecture: Evidence and Probability Before Pascal (Baltimore: Johns Hopkins University Press, 2001), 6.</ref> The same concept was found in ancient Roman law, where, for example, if there was doubt as to whether a child was really the issue of someone who had left money in a will, the presumption was in favour of the child.<ref>Franklin, Science of Conjecture, 9.</ref> Medieval Roman and canon law graded presumptions according to strength: light, medium or probable, and violent.<ref>Franklin, Science of Conjecture, 20–23.</ref> These gradings and many individual presumptions were taken over into English law in the seventeenth century by Edward Coke.<ref>Franklin, Science of Conjecture, 60–61.</ref>

There are two types of presumption: rebuttable presumption and conclusive presumption. An example of presumption without basic facts is presumption of innocence.<ref>Technically, the presumption of innocence is not a presumption, but rather is a rhetorical expression that emphasizes that the prosecution bears the burden of proof in a criminal case. The accused has no obligation to adduce evidence in their favor and is automatically acquitted unless the prosecution proves guilt beyond a reasonable doubt. See presumption of innocence.</ref>

An example of presumption with basic facts is Declared death in absentia, e.g., the law says if a person has been missing for seven years or more (basic fact), that person is presumed dead.{{ safesubst:#invoke:Unsubst||date=__DATE__ |$B= {{#invoke:Category handler|main}}{{#invoke:Category handler|main}}[citation needed] }}

Presumed sections