If you're talking straight law:
4 subjects - usually 3 hours each (4 hours after week 6, which is when tutorials start) = 12 contact hours a week, upped to 16 contact hours a week when tutes start.
Commerce/law:
Usually 2 commerce 2 law. Don't know what contact hours are like since I don't do it.
You are expected to do ~4-6 hours of personal study for every contact hour in law. And you'll need that time if you plan on reading every single case you are expected to.
You generally do most of the compulsory/core subjects before you tackle electives, as a lot of them have pre-requisities.
ISN'T like Negligence and Criminal Law etc. covered in Legal Studies 1/2 + 3/4... wouldn't I just be re-learning what I've learnt in Year 11 and 12.
Please be joking...