Additional Rules of Evidence

The best evidence rule

The best evidence rule is a reminder to preserve original documents for production in court. The rule is part of the common law but it remains applicable to the extent that it is consistent with the provisions, and promotion of the purpose and principles, of the EA (refer sections 10 and 12). This means that it should be approached as a guideline rather than a strict requirement, since the overriding objective is ensuring that all relevant and reliable evidence is admitted.

Where copies of original documents are involved, reliability is the main test of admissibility: in other words, where a copy is reliable, it is likely to be admitted. Manual copying should be supported by evidence of the copying process to establish reliability. An automatic copying device or technical process will not require proof that a copy is accurate, if it ordinarily does what is asserted (refer s137 of the EA). The defence may, however, raise evidence of inaccuracy or intervention in the process (e.g., that digital photographs were copied and modified).

Note that photographs may be enhanced or otherwise modified and remain admissible, if the purpose of that enhancement is fair and relevant and can be clearly understood by the Court. For this reason the original should always be kept to allow your purpose to be tested.

Disclosure of information

A prosecutor has a duty to disclose to the defendant any file notes and other documents relating to the prosecution. Communications between the local authority and its lawyer are excepted, as these are protected by solicitor-client privilege. Sections 51 to 67 of the EA contain further information about privilege.

The duty of the prosecution to disclose information to the defence was established by the provisions of the Official Information Act 1982 the decisions in Commissioner of Police v Ombudsman [1988] 1 NZLR 385(also reported as Pearce v Thompson [1988] 3 CRNZ 268) effectively places an obligation on the prosecution to supply to the defendant copies of briefs of evidence, witnesses' statements and interview notes on request. Such information is ‘personal information’ under the Act, and the defendant has a statutory right to request it.

If the local authority takes enforcement action other than prosecution, the party against whom the action is taken can make a request under the Local Government Official Information and Meetings Act 1987. Copies of documents on the local authority file will then have to be provided, unless there are reasons for withholding the information under sections 6 and 7 of the Local Government Official Information and Meetings Act.

Publishing enforcement action

Prejudice to the defendant

Defendants prosecuted under the RMA for offences against s338(1) have a right to elect trial by jury. A company prosecuted under the RMA has a right to elect trial by jury even though the company itself cannot be sentenced to imprisonment. If a local authority prosecutes and there is a media report about the prosecution, this could influence the jury and prejudice the right of the defendant to a fair trial. It may take some time for the defendant to make a decision as to whether or not to elect trial by jury.

  • Local authorities should not issue press releases on prosecutions other than with very general details of the case, and without identification of the defendants.


Generally public comment is not made about a case when it is still before the Courts and the determination of guilt or innocence is yet to be made. The media do, however, report about matters before the Court makes a decision but need to comply with the Environment Court Media Coverage Guidelines 2011 [Ministry of Justice website]

  • In press releases about any enforcement matters before a Court decision, it should be clear the local authority is taking enforcement action in respect of an alleged breach of the RMA. For a case law example, see Manawatu-Wanganui Regional Council v Lakeview Farm Fresh Ltd [2000] CRN 9031005197-205 .