Road Traffic Act 1974

A person to whom section 64A(1) applies who drives or attempts to drive a motor vehicle while having any blood alcohol content commits an offence.

A person who drives or attempts to drive a motor vehicle to which section 64A(4) applies while having any blood alcohol content commits an offence.

Subsection (2) does not apply to a person who drives or attempts to drive a motor vehicle described in section 64A(5)(a) or (d) if the person —

is a person of a class prescribed by the regulations for the purposes of this paragraph; and

is driving or attempting to drive the vehicle in the course of responding to an incident as defined in the Fire and Emergency Services Act 1998 section 3.

It is a defence to a charge of an offence against subsection (1) or (2) for the accused to prove that the accused’s blood alcohol content was not to any extent caused by any of the following —

the consumption of an alcoholic beverage (otherwise than for the purposes of religious observance);

the consumption or use of any other substance (for example, food or medicine) for the purpose of consuming alcohol.