In Qld. you can't sleep in the front compartment, and even if you sleep in the back, you will have to prove you are not ‘in charge’. So even if the police haven't seen you driving, just by being in the car under the influence of alcohol or drugs (remember, zero alcohol if you are on a learner, provisional, probationary or restricted licence), you risk being charged with breaking the law. Of course there will be local council bylaws that also apply.