Here is an interesting take on a jurisdictional point, from the Northern Territory.
Broadly, the view that the courts have typically taken on judicial reviews of adjudicators’ decisions is that if the decision is defective in any one respect, the whole decision is quashed. In other words, one bad apple ruins the whole barrel.
But what if the adjudication concerns more than one dispute? In the Northern Territory, section 34 allows adjudication of multiple disputes, subject to consent:
(3) An appointed adjudicator may:
(a) with the Registrar’s consent, extend the time for making a determination under section 33(1); or
(b) with the consent of the parties, adjudicate simultaneously 2 or more payment disputes between the parties; or
(c) with the consent of all the parties concerned, adjudicate the payment dispute simultaneously with another payment dispute.
In M & P Builders v Norblast  NTSC 25, the adjudicator dealt with three disputes, and found for the claimant in all of them. But one was without jurisdiction: the adjudication application had been made prematurely, and so there was no jurisdiction to deal with that one.
Was the whole determination thus void? No. The court quashed the determination in respect of that one dispute, but allowed the other two to stand.