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 includes a rebuttable discretionary presumption, a rebuttable mandatory presumption, and an irrebutable or conclusive presumption. The invocation of a presumption will normally shift 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.
example of presumption with basic facts: Presumption of death, e.g law says if a person has missing for 7 years or more (basic fact), that person shall be presumed to be dead.