The offence of DUI or Driving Under the Influence of intoxication liquor or a drug is created by section 112(1) of the Road Transport Act 2013 and states as follows:
(1) A person must not, while under the influence of alcohol or any other drug:
(a) drive a vehicle, or
(b) occupy the driving seat of a vehicle and attempt to put the vehicle in motion, or
(c) being the holder of a driver licence (other than a provisional licence or a learner licence issued under the Road Transport (Driver Licensing) Act 1998 ), occupy the seat in or on a motor vehicle next to a holder of a learner licence who is driving the motor vehicle.
It can be seen therefore in respect of a DUI offence involving alcohol, that a person might not be over the prescribed limit of 0.05 and yet driving under the influence of alcohol (DUI). There must be some observed signs by a witness that in their opinion, the person was so affected, that the court can draw the inference that the person was driving under the influence of alcohol (DUI).
Such observations of erratic driving, combined with observations of the person displaying outward signs such as being unsteady on his feet, bloodshot eyes, slurring his words, having trouble putting the key into the ignition etc. all combine to conclude that the person was driving under the influence (DUI).
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