This case is a good reality check for employers and employees involved in serious Fair Work disputes. Section 570 usually limits costs orders in Fair Work matters, which is why people sometimes describe the jurisdiction as a no-costs or low-costs risk environment. That shorthand is dangerous. The section still allows costs where conduct is unreasonable in the statutory sense.
The Court did not punish Mr Roohizadegan simply because he lost. The history mattered. He had earlier success and the Full Court had ordered a retrial. But by the time of the later offer, the evidence and litigation risk had changed. The Court pointed to the very wide pleading, the multiplication of allegations, the large quantum assumptions, the extra evidence and expert work those choices caused, and the failure to engage with a substantial settlement offer made after much of the trial evidence had unfolded.
For businesses, the lesson is to treat settlement offers as live risk documents. If you are defending a Fair Work claim, make offers carefully and explain the commercial basis. If you are bringing or defending a claim, keep reassessing the case as evidence changes. A claim that was arguable at the start can become unreasonable to continue in the same form.