New South Wales Consolidated Acts New South Wales Consolidated Acts(cf Traffic Act s 5AB (1))
In proceedings for an offence under section 12 (1):
(a) evidence may be given of:(i) the presence of a drug, or(ii) the presence of a particular concentration of a drug,in the blood or urine of the person charged, as determined pursuant to an analysis under Division 3A, 4, 4A or 5 of a sample of the person’s blood or urine, and
(b) the drug the presence of which is so determined or the particular concentration of the drug the presence of which is so determined, as the case may be, is to be taken to have been present in the blood or urine of that person when the event referred to in section 12 (1) (a) or (b) (as the case may be) occurred,if the sample was taken within 4 hours after the event, unless the defendant proves the absence of the drug, or the presence of the drug in a different concentration, when the event occurred.