The following extract from a Fair Work Commission case exemplifies the approach b y the Commission to the rules of evidence which apply in Australian courts.
“We note the comments of the Full Bench in Hail Creek Coal Pty Ltd v Construction, Forestry, Mining and Energy Union (2004) 143 IR 354;  AIRC 670 (‘Hail Creek’) at :
‘ While the Commission is not bound by the rules of evidence that does not mean that those rules are irrelevant. As the then President of the Industrial Relations Commission of Western Australia said in respect of a similar provisions in the then Industrial Relations Act 1979 (WA):
“However, this is not a licence to ignore the rules. The rules of evidence provide a method of enquiry formulated to elicit truth and to prevent error. They cannot be set aside in favour of a course of inquiry which necessarily advantages one party and necessarily disadvantages the opposing party (R. v War Pensions Entitlement Appeal Tribunal: ex parte Bott  50 CLR 228 Evatt J. at 256 (dissenting)). The common law requirement that the Commission must not in its reception of evidence deny natural justice to any of the parties acts as a powerful control over a tribunal which is not bound by the rules of evidence.”’ (footnotes omitted)
 Counsel put that, in in any event, s 590 of the Act which goes to the Commission being able to inform itself ‘in such manner as it considers appropriate’, does not limit how the Commission may inform itself, and does not prevent the Commission from accepting evidence, which is obtained improperly or unlawfully; see: Hail Creek.”
Krav Maga Defence Institute Pty Ltd t/a KMDI v Markovitch (2019) FWCFB 4258 – 19 June 2019 – Sams DP, Gostencnik DP and McKinnon C