In "D'Emden v Pedder" (1904), the High Court formulated a doctrine of implied immunity of instrumentalities, modelled closely on the American concept of intergovernmental immunity which Barton and the other authors of the constitution had closely studied. The court followed this precedent in "Deakin v Webb" (1904), which was subsequently overturned by the Judicial Committee of the Privy Council in "Webb v Outtrim" (1906). Barton was angered by the Privy Council's intervention, having always believed the High Court should be the final court of appeal. In personal correspondence he described the 83-year-old presiding judge Lord Halsbury as an "old pig" who did not understand the needs of a federation.