Police Powers and Responsibilities Act 2000

The responsible officer must immediately take the steps the officer considers to be reasonably necessary to protect anything at the crime scene from being damaged, interfered with or destroyed, including for example, steps necessary—

to ensure people, including police officers, whose presence at the crime scene is not essential do not enter the crime scene; and

to prevent unnecessary movement inside the boundaries of the crime scene; and

to establish a safe walking area in the crime scene for reducing the risk of damage to any evidence that may be on the place.

Also, a person, other than the responsible officer, must not enter a crime scene unless—

the person has a special reason, associated with the investigation, for entering the crime scene; or

the person is a police officer who is asked to enter the crime scene by the responsible officer or an investigating police officer; or

the person is an authorised assistant; or

the presence of the person is necessary to preserve life or property at a crime scene; or

the person is authorised to enter by the responsible officer.

For subsection (2)(e), the responsible officer may authorise the entry subject to stated requirements.

The responsible officer must ensure a record is made of the name of each person who is present when the crime scene is established or enters it after it is established, when each person entered the place after it is established, and the purpose of the entry.