Most digital evidence in Australian proceedings is never formally challenged — until the matter where it is. Under the uniform evidence law (the Evidence Act 1995 (Cth) and its NSW, Victorian, Tasmanian, ACT and NT counterparts), electronic material faces the same gateways as any other evidence: relevance, authenticity, hearsay, opinion, and the discretionary exclusions. Queensland, Western Australia and South Australia retain their own evidence statutes — in Queensland, the Evidence Act 1977 (Qld) — so the section numbers below apply in uniform-law jurisdictions, though the underlying principles travel. Where digital evidence differs is how easily each gateway can be attacked when the material was collected informally.
Relevance and Authenticity
Sections 55–56 set a low relevance bar, but authenticity is where digital exhibits are lost. The question is not "is this a real document" but "is this what it purports to be, produced by the process claimed". Section 146 presumes that documents produced by machines functioning normally are accurate — a presumption that survives only while your side can describe the machine and the process. If the collection was an office worker forwarding emails to themselves, expect the presumption to be tested.
Hearsay and the Business Records Exception
Much electronic material — system logs, transaction records, CRM entries — comes in through S 69 as business records. The exception depends on the record being made in the course of business from knowledge of the asserted fact. Metadata that shows when and how a record was created is often what makes the s 69 argument, which is another reason forensic collection matters: informal copies strip that metadata away.
The Discretions: Ss 135 and 138
Even relevant, authentic material can be excluded where its probative value is substantially outweighed by the danger of unfair prejudice (S 135) or where it was improperly or illegally obtained (S 138). Evidence pulled from a former employee's personal device without authority, or captured in breach of surveillance devices legislation, invites a s 138 fight you may not win.
Before You Rely on It, Confirm:
If any answer is uncertain, an independent examination before filing is far cheaper than an admissibility fight at hearing.
Frequently Asked Questions
What Determines Whether Digital Evidence Is Admissible in Australian Courts?
Under the uniform evidence law, digital material faces the same gateways as any other evidence: relevance (Ss 55–56), authenticity, the hearsay rule and its exceptions (including the S 69 business-records exception), and the discretionary exclusions (Ss 135 and 138). Queensland, Western Australia and South Australia apply their own evidence statutes, with similar underlying principles.
Can Improperly or Illegally Obtained Digital Evidence Still Be Admitted?
Possibly. Section 138 is a discretion, not an automatic exclusion: improperly or illegally obtained evidence is excluded unless the desirability of admitting it outweighs the undesirability of how it was obtained. It is a fight the tendering party may not win — which is why collection authority matters from the outset.
Why Does Informal Collection Put Digital Evidence at Risk?
Informal copies — forwarded emails, drag-and-drop file copies — strip the metadata that supports the S 146 presumption of accuracy for machine-produced documents and the S 69 business-records argument. Forensic collection, with hash values recorded at acquisition, preserves both.