This article argues that the cultural self-understandings of the judiciary can exert a profound effect on legal outcomes under a bill of rights. Utilizing the case of New Zealand, it demonstrates that confinement of expansive case law under the New Zealand Bill of Rights (NZBOR) to the criminal law and freedom of expression arenas is most significantly explained by a British-descended judicial culture that prioritizes, first, those civil liberty values already cognizable by the common law and, second, rights connected with the policing of parliamentary and legal processes. Nevertheless, judicial culture does not operate in a vacuum. Rather, the opportunity structure facing potential public interest litigants under NZBOR depends also on their politicolegal resource set including the attitude of the political branches (legislature and executive) to the claim being forwarded.