The Union Steam Ship Co of New Zealand (Union) was prosecuted by the Northland Harbour Board (the Harbour Board) for the offence of discharging oil from the ship Athelviscount into the Whangarei Harbour on 25 December 1974. The prosecution was heard in the Magistrate's Court in December 1975. The Magistrate was satisfied there had been a spillage of oil for the purpose of the Marine Pollution Act 1974 (the Act), but that it was an escape of oil and not a discharge of oil. It was common ground between the parties that the cause of the spillage was a fractured pipe in one of the tanks.

The Harbour Board appealed to the Supreme Court where the appeal was allowed. Speight J held that the Magistrate's decision was erroneous in point of law and referred the case back to the Magistrate's Court for determination. Special leave was given to Union to appeal to the Court of Appeal.

Held: Appeal dismissed.

Richmond P: The Harbour Board's argument is based on s 2(3) of the Act which provides:

Any reference in this Act to the discharge or escape of oil or any pollutant or to any oil or pollutant being discharged, from any ship or offshore installation or place or thing or pipeline or apparatus, or as the result of any of the operations mentioned in s 5 of this Act (except where the reference is to its being discharged for a specified purpose) includes, but is not limited to, spilling leaking, pumping, pouring, emitting, or emptying of that oil or pollutant, as the case may be, howsoever it is caused and howsoever it occurs; but does not include dumping.

The Act is described in its long title as 'an Act to make better provision for preventing and dealing with pollution of the sea, and to enable effect to be given to certain International Conventions relating thereto'. These Conventions include the International Convention on Civil Liability 1969 (the CLC 1969). Part IV of the Act deals with the question of civil liability and the operative sections use the expressions 'is discharged or escapes' and 'the discharge or escape'. To this extent, they follow the language of the CLC 1969.

An allegation of 'discharge or escape' in the alternative would support a conviction based on the extended meaning set out in s 2(3) of the Act.

Cooke J: Union argues that the leakage of oil was an escape not a discharge. However, references to oil 'being discharged' is wide enough to include what may be described, and was described by the Magistrate, as an escape. There is no ambiguity in that extended definition. If oil is 'discharged' an offence is committed.

McMullin J: It would be inconsistent with the purpose of an Act which is 'to make better provision for preventing and dealing with pollution of the sea, and to enable effect to be given to certain International Conventions relating thereto' that the wide definition given to discharge under the Oil in Navigable Waters Act 1965 should be narrowed. Speight J was right in the interpretation which he placed on the section. The appeal must be dismissed.