A driver is not permitted to drive with any illicit substance in their system. The use of medicinal marijuana whilst driving would constitute a drug driving offence under the Road Traffic Act 1961 – not withstanding any information obtained from your Medical Practitioner. Medicinal marijuana contains a ‘prescribed drug’, THC, which must not be present in a driver’s oral fluid or blood.
s 47BA(1) Road Traffic Act 1961
s 16(a) Road Traffic (Miscellaneous) Regulations 2014