Oshlack v Richmond River Council

Oshlack, the applicant, sought judicial review of a decision by the Richmond River Council, the respondent, to grant development consent for a residential subdivision. The applicant contended that the Council had failed to take into account a relevant consideration, namely the potential impact of the development on the endangered Richmond Birdwing butterfly. The matter came before the High Court of Australia.

The central legal issue before the High Court was whether the Council, in granting development consent, had failed to consider a relevant consideration under section 94(1) of the Environmental Planning and Assessment Act 1979 (NSW). Specifically, the Court had to determine if the potential impact on the Richmond Birdwing butterfly was a matter that the Council was bound to consider, and if its failure to do so rendered the consent invalid.

The High Court held that the Council had a duty to consider the potential impact on the Richmond Birdwing butterfly. Brennan CJ, Toohey and Gummow JJ reasoned that the species' endangered status, coupled with the likely impact of the development on its habitat, made it a relevant consideration for the Council. The Court found that the Council's failure to adequately address this matter constituted a failure to take into account a relevant consideration, thereby vitiating the development consent. The Court applied the principles of administrative law concerning the proper exercise of statutory power, emphasizing that decision-makers must consider all relevant factors prescribed or implied by the governing legislation.

The High Court ordered that the development consent granted by the Richmond River Council be quashed.