Sitting as the Court of Disputed Returns, Barton was the sole judge in "Blundell v Vardon" (1907), where he ruled that Joseph Vardon's election to the Senate was void due to electoral irregularities. He joined with Griffith and O'Connor in the majority opinion in "R v Barger" (1908), "the High Court's most decisive intervention to date in thwarting social reforms passed by the Commonwealth parliament". In a series of cases around the same time, the trio also restricted the powers of the Commonwealth Court of Conciliation and Arbitration. Barton and Griffith split notably in "New South Wales v Commonwealth" (1915), with the court voting 4–2 to strip the Inter-State Commission of any judicial power, much to Barton's dismay. Only Gavan Duffy sided with his argument that parliament should determine the commission's powers rather than the court. The decision was "a rebuff to Barton's authority as an interpreter of the Constitution and his special authority as one of its draftsman".