actually, to clarify, the road rules actually say that you can overtake in the left lane, but only if the following are true:
1. Speed limit is 80km/h or less
2. There is no "keep left unless overtaking" sign
3. There are lane markings
4. It is safe to do so.
On roads with speed limits above 80km/h it is implicit that you keep left unless overtaking
On roads with no lane markings, you must overtake on the right
Regardless, when turning right at an intersection you should always turn into the right-hand most lane unless the road markings indicate different
I'm not commenting on what happened, just stating the facts as I read them in the vicroads handbook so we can all be better informed drivers.
end of lesson