Further to my brief post two weeks ago linking to Grahame Orr’s piece on the WA Senate Election case on The Conversation, Professor Anne Twomey of the University of Sydney has posted ‘Missing Votes Means It’s Back to the Polls for Western Australia’ late yesterday on The Conversation. There is also a longer version of this post available on Sydney’s Constitutional Critique blog that goes into more detail about the facts of the case, the workings of the Court of Disputed Returns, and the decision itself. While several high profile electoral law cases have ended up before the High Court in recent years (Unions NSW v New South Wales  HCA 58; Rowe v Electoral Commissioner  HCA 46; Roach v Electoral Commissioner  HCA 43; Mulholland v Australian Electoral Commission  HCA 41), these have concerned constitutional issues around voting rights (Roach and Rowe) the registration of political parties (Mulholland) or electoral funding (Unions NSW), rather than the contestation of electoral results themselves before the Court of Disputed Returns. Given the rarity of its operation, it is all the more helpful to have timely expert commentary on the workings of the Court of Disputed Returns.
Twomey notes an issue that many readers will have considered: can Hayne J’s decision be appealed to the Full Court?
Section 368 states that all decisions are final and cannot be appealed. While a previous challenge to the constitutional validity of this provision has failed in relation to the determination of a challenge by the Federal Court (Smith v AEC  FCAFC 43), there is still the possibility that it could be challenged as unconstitutional in relation to appeals from a single Justice of the High Court to the Full Bench.
There is no indication yet that any of the parties intend to mount a constitutional challenge to s 368, though as noted in Twomey’s post and on our case page, Justice Hayne will convene the Court again tomorrow morning and hear the parties on ‘any remaining issues’. If a challenge is to be made, it will be raised tomorrow.
In the meantime, there is some High Court dicta on the validity of s 368, from Sue v Hill  HCA 30, which involved a challenge to the election of a federal Senator who had recently become a dual Australian and British citizen on the basis that she was a ‘citizen of a foreign power’ and therefore barred from election by s 44(i) of the Commonwealth Constitution. Various judges made reference to the operation and effect of s 368. Gaudron J noted
The effect of s 368 is that, if a petition is heard and determined by a single Justice or a single Judge of a court to which a petition may be referred pursuant to s 354(1) of the Act, there is no appeal. Nor is there an appeal if the jurisdiction is exercised by a court comprised of more than one Justice or Judge. That consequence is entirely consistent with s 73 of the Constitution by which appellate jurisdiction is relevantly conferred on this Court with respect to judgments and orders of a single Justice and other courts exercising federal jurisdiction but ‘with such exceptions and subject to such regulations as the Parliament prescribes’. That being so, the absence of appellate review says nothing as to the character of the power conferred by s 360 of the Act.
Gleeson CJ, Gummow and Hayne JJ noted at :
As Gaudron J has pointed out, in its application to the appellate jurisdiction of this Court, s 368 is to be supported as a prescription by the Parliament of an exception within the meaning of s 73 of the Constitution. However, were it not for the availability of the procedures under s 18 of the Judiciary Act, particularly with respect to questions arising under the Constitution or involving its interpretation, a question may have arisen as to the validity of s 368.
On the plurality’s reading the power given to a single Judge of the Court of Disputed Returns under s 18 of the Judiciary Act 1903 (Cth) to refer the case to the Full Bench precludes any appeal if that judge declines to do so and instead decides the case.
In Sue v Hill, Gleeson CJ and Callinan J sat as judges of the Court of Disputed Returns and did state a case for the Full Court to answer. While the parties in AEC v Johnson might have preferred that Hayne J had made just such a referral, it does not seem that his decision can be appealed. If a challenge to s 368 were to be raised, Hayne J could, in theory, refer that challenge to the Full Court under s 18 as a question for the Full Court’s consideration. But given the statements in Sue v Hill by four judges, including Hayne J himself, indicating that s 368 is constitutional that outcome seems unlikely. In any case as noted by Hayne J in Johnson at , the parties have accepted that voiding the election would be the appropriate outcome:
All parties rightly accepted that, if the Court declares that Mr Dropulich and Senator Ludlam were not duly elected, and cannot declare who was duly elected, the only relief appropriate is for the election to be declared void.
Absent one of the parties reneging on that acceptance, the only real ‘remaining issue’, then, appears to be declaring the election void.