Relevance as the gateway. Evidence is relevant if, were it accepted, it could rationally affect the assessment of the probability of a fact in issue directly or indirectly (s 55(1)). Relevance may be established provisionally, including on the undertaking that further evidence will make a finding of relevance reasonably open (s 57). If evidence passes this threshold it is admissible unless an exclusionary rule applies; if it fails, it must be excluded (s 56).
Hearsay and first-hand distinctions. The hearsay rule prohibits evidence of a previous representation to prove an asserted fact that the person can reasonably be supposed to have intended to assert (s 59). The rule does not apply if the evidence is admitted for a non-hearsay purpose, but in a criminal proceeding this non-hearsay use exception is not available for an admission (s 60(3)). First-hand hearsay exceptions in Division 2 of Part 3.2 are confined to representations made by a person with personal knowledge, meaning knowledge based on what they saw, heard or otherwise perceived, not on another’s representation (s 62). Civil and criminal proceedings are treated asymmetrically: in civil proceedings a first-hand hearsay representation is admissible if the maker is unavailable (s 63), or if the maker is available but calling them would involve undue expense, delay or is not reasonably practicable (s 64(2)). In criminal proceedings the maker’s unavailability triggers narrower gateways, including representations made under a duty, shortly after the fact in circumstances unlikely to be a fabrication, in circumstances making it highly probable the representation is reliable, or against the maker’s interests (s 65(2)). Where the maker is available and called, the asserted fact must have been fresh in the memory (s 66). Additional exceptions cover business records (excluding documents prepared for proceedings or criminal investigations, s 69(3)), electronic communications, tags and labels, traditional laws and customs of Aboriginal and Torres Strait Islander peoples, reputation and interlocutory proceedings (ss 70-75). Notice in writing is generally required (s 67), with a procedure for objection and potential cost penalties for unreasonable objection in civil cases (s 68).
Opinion. The opinion rule excludes evidence of an opinion to prove a fact about which the opinion was expressed (s 76). Exceptions include evidence used for a non-opinion purpose (s 77), lay opinion necessary for an adequate account (s 78), opinions based on specialised knowledge (training, study or experience, explicitly including child development and sexual abuse, s 79(2)), and traditional laws and customs (s 78A). The ultimate issue and common knowledge rules are abolished (s 80).
Admissions. An admission is exempt from both the hearsay and opinion rules (s 81). However, the admission must be first-hand unless contained in a document (s 82), cannot be used against a third party without consent (s 83), and is subject to specific exclusionary rules: if influenced by violent, oppressive, inhuman or degrading conduct (s 84); if the truth of a defendant’s admission to an investigating official was likely adversely affected (s 85); or if a documentary record of oral questioning by an official is not acknowledged by the defendant as true (s 86). A representation may be treated as an admission if it is reasonably open to find it was made with authority, by an employee within scope or in furtherance of a common purpose (s 87). In criminal proceedings, no unfavourable inference may be drawn from a party’s silence in response to an investigating official’s questioning, and evidence that could only be used to draw such an inference is inadmissible (s 89). The court may refuse to admit prosecution evidence of an admission if it would be unfair to the defendant (s 90).
Tendency and coincidence. Evidence of character, reputation, conduct or tendency is not admissible to prove a person acted in a particular way or had a particular state of mind unless reasonable written notice is given and the court considers the evidence has significant probative value (s 97). The coincidence rule operates similarly for evidence of two or more events offered to prove that a person did an act or had a state of mind on the basis of the improbability of coincidence (s 98). In criminal proceedings, tendency or coincidence evidence adduced by the prosecution about a defendant faces an additional restriction: its probative value must substantially outweigh any prejudicial effect (s 101(2)).
Credibility. Credibility evidence is defined as evidence relevant to credibility that is either relevant only for that purpose or is relevant for that purpose and for another purpose for which it is not admissible under Parts 3.2 to 3.6 (s 101A). The credibility rule renders such evidence inadmissible (s 102), subject to exceptions for cross-examination that could substantially affect credibility (s 103), rebuttal of denials with leave (s 106), re-establishing credibility in re-examination or by prior consistent statements (s 108), and evidence of a person with specialised knowledge about credibility given with leave (s 108C). Specific provisions protect an accused person from cross-examination on credibility unless the prosecution meets certain gateways and leave is granted (s 104).
Character. In criminal proceedings only, a defendant may adduce evidence of good character without being restricted by the hearsay, opinion, tendency or credibility rules (s 110). Once raised, those rules do not apply to evidence adduced to prove the defendant is not of good character in that respect; cross-examination on character requires leave (s 112).
Identification evidence. In criminal proceedings, visual identification evidence adduced by the prosecutor is not admissible unless an identification parade was held, it was not reasonable to hold one or the defendant refused, and the identification was made without intentional influence (s 114). Picture identification evidence is similarly restricted, especially when the defendant was in custody (s 115). The judge must direct the jury on the special need for caution (s 116).
Privileges. Client legal privilege protects confidential communications and documents made for the dominant purpose of legal advice (s 118) or litigation (s 119), with analogous protection for unrepresented parties (s 120). Privilege is lost through consent or inconsistent conduct (s 122), joint client arrangements (s 124), or if made in furtherance of fraud, an offence, a civil penalty or a deliberate abuse of power (s 125). Journalist privilege protects the identity of an informant to whom a promise of confidentiality has been given; the journalist and their employer are not compellable to disclose it, but the court may override the privilege if the public interest in disclosure outweighs the adverse effect and the public interest in news media’s access to sources (s 126K). A member of the clergy may refuse to divulge a religious confession, unless it was made for a criminal purpose (s 127). A witness may object to giving evidence that may prove an offence or expose them to a civil penalty; if grounds are established the court must not require the evidence to be given unless it relates only to a foreign law and the interests of justice so require (s 128). In either case the witness receives a certificate that prevents the evidence and its derivatives being used in Australian proceedings, except for falsity or a retrial (s 128(5), (7), (9)). A special sealed-envelope procedure applies to disclosure orders made in federal court civil proceedings as part of freezing or search orders (s 128A). Bodies corporate are expressly denied the privilege against self-incrimination (s 187). Evidence may also be excluded on public interest grounds concerning reasons for judicial decisions (s 129), matters of state (s 130) and settlement negotiations (s 131).
Discretionary and mandatory exclusions. The court has a general discretion to exclude evidence if its probative value is substantially outweighed by the danger of unfair prejudice, confusion or undue waste of time (s 135) and to limit the use of evidence (s 136). In criminal proceedings, the court must refuse to admit prosecution evidence if its probative value is outweighed by the danger of unfair prejudice to the defendant (s 137). Evidence obtained improperly or illegally is not to be admitted unless the desirability of admission outweighs the undesirability (s 138), with related cautioning rules affecting whether evidence is taken to have been improperly obtained (s 139).
Facilitative proof and procedural machinery. Part 4.3 creates rebuttable presumptions for devices and processes (ss 146, 147), seals and signatures (ss 150, 151), ancient documents (s 152), official gazettes and documents (ss 153-158), posts and electronic communications (ss 160-163), and other matters, reducing the need for formal proof. The standard of proof for admissibility questions is the balance of probabilities; the court must consider the importance of the evidence and the gravity of the matters alleged (s 142). Part 4.5 requires judicial warnings about potentially unreliable evidence on request (s 165), and imposes strict limits on warnings about children’s evidence: a judge must not give a general warning that children are unreliable or that their evidence requires more scrutiny than that of adults (s 165A). Where a defendant has suffered a significant forensic disadvantage because of delay, the judge must inform the jury of the nature of the disadvantage, though must not suggest it is dangerous or unsafe to convict on that account alone (s 165B). Part 4.6 provides mechanisms for requests to produce documents or call witnesses (Div 1), proof by affidavit or written statement (Div 2), foreign law (Div 3) and certificates of expert evidence, convictions and service (Div 4). Chapter 5 rounds out the scheme with provisions for Commonwealth records and documents (s 182), voir dire (s 189), waiver of rules of evidence by consent (s 190, excluding Parts 3.9, 3.10 and 3.11), agreed facts (s 191), leave on terms (s 192, requiring the court to consider hearing length, unfairness, importance of evidence, the nature of the proceeding and the power to adjourn), advance rulings (s 192A) and the offence of publishing disallowed questions (s 195).