Assuming we are talking about illicit substances like cocaine, Mdma or marijuana, then yes, it is illegal to have these drugs in your system. Obviously, if they are in your system then you have been using them, which is illegal.
If you are drug tested while driving or any other offense then you will be charged for having these drugs in you.
Having drugs in your system is illegal in;
- New South Wales
- Australian Capital Territory
- South Australia
- Western Australia
- Northern Territory