23 (1) If a port authority or a wholly-owned subsidiary of a port authority is acting as agent of Her Majesty in right of Canada, the port authority or subsidiary must fulfil or satisfy an obligation or liability in respect of the port authority or subsidiary, as the case may be, arising from its exercise of, or its failure to exercise, a power or right or arising by operation of law. Her Majesty is not responsible for fulfilment or satisfaction of the obligation or liability, except that if a judgment or decision is rendered by a court of competent jurisdiction in respect of the obligation or liability, Her Majesty is responsible for satisfying the judgment or decision to the extent that it remains unsatisfied by the port authority or subsidiary at least thirty days after the judgment or decision becomes final.