Clearly he didn't. But instead of saying 'I don't know' or 'I'm not sure', he instead stalled for time with his patented double speak until someone finally explained it.
The Separation of Powers under the Westminster System basically means that the branches of legislature, executive and judiciary must act separately and not be allowed to encroach on each other. It's a pity Sir Joh apparently didn't understand this because it is exactly what his government were being accused of breaching.
As part of my job I have to listen to a lot of political commentary and it amazes me how difficult it is for politicians to answer a question directly. One of the great question-avoiders in interviews I encountered before she became PM was Julia Gillard. She would always turn questions back to the official party line rather than risk drifting off topic and making a controversial statement, especially when it came to rumours of a leadership spill.
Maybe this skill to confound rather than enlighten is something that has helped politicians such as Sir Joh and Julia Gillard (strange that they are at polar ends of politics) gain power. I can't blame Ms Gillard in a way, because when she went to the last election with a promise not to introduce a carbon tax she was labelled a 'liar' when Labor introduced one. No politician wants that!
This week Federal Coalition Leader Tony Abbott accused the carbon tax of being a reason why BHP pulled out off the Olympic Dam project before admitting on national TV that he had not even read the report. Later he retracted this statement. I'm still unsure whether he has read it or not but it does undermine his claim to be able to have an informed opinion on this issue. Here Abbott admitted he 'didn't know' which is to his credit I suppose, but his shrugging 'aw shucks - you caught me out' persona following his gaff and subsequent spin was equally annoying.
It seems that all political commentary is spin these days and having to listen to it can be very frustrating. I often feel as frustrated as this British interviewer Jeremy Paxman ,who asked the same question 'Did you threaten to overrule him?' a dozen times in this brief interview with conservative politician Michael Howard and still didn't get a straight answer.