Short answer. Evidence is the means sanctioned by the Rules for ascertaining, in a judicial proceeding, the truth respecting a matter of fact. Rule 128, Section 1 frames it as a tool for fact-finding — whatever method the Rules recognize as legitimate for establishing what actually happened is, by definition, evidence.
What the law says
Evidence is the means
Rule 128, Section 1 — Evidence defined. Read the full provision →
What the law says
of ascertaining in a judicial proceeding the truth respecting a matter of fact.
Rule 128, Section 1 — Evidence defined. Read the full provision →
Evidence defined by its function
Section 1 defines evidence not by listing categories, but by what it is for: it is the means of ascertaining, in a judicial proceeding, the truth respecting a matter of fact. The definition is functional — evidence is whatever legitimately serves that fact-finding purpose within the framework the Rules sanction. This functional framing sets the stage for everything that follows in the rules on evidence, which spell out which specific means qualify and how they may be used.
Why 'sanctioned' matters
The definition ties evidence to means that are sanctioned — authorized or recognized — by the Rules. Not everything that might inform a person's belief about what happened qualifies as evidence in the legal sense; it must fit within the methods the rules of evidence themselves recognize as legitimate. This is why the rules on evidence carefully define categories like object, documentary, and testimonial evidence, and the conditions under which each may be admitted.
Truth about a matter of fact, in a judicial proceeding
The definition is also confined to judicial proceedings and to matters of fact, as opposed to questions of law, which courts resolve through legal argument and authority rather than evidence in this sense. This framing sets up the rest of the rules on evidence, which govern which sanctioned means may be used and how. Facts about foreign countries or general knowledge the court may separately notice under the rules on judicial notice, discussed elsewhere in this same rule, work somewhat differently.
How this opening definition sets up the rest of the rules
Because Section 1 defines evidence functionally rather than by an exhaustive list, the provisions that follow throughout the rules on evidence do the more detailed work of specifying which particular means — object evidence, documentary evidence, testimonial evidence, and the various rules on admissibility, competence, and weight — actually qualify as sanctioned methods of establishing a fact. This opening section is the foundation those later, more specific provisions build on. This foundational definition does not by itself decide whether any particular piece of evidence will actually be admitted in a given case; admissibility depends on the further, more specific rules on relevance and competence that build on this opening section rather than on the definition standing alone.