Advice documents mostly sacrosanct

A couple of weeks ago Minister for Climate Change Penny Wong was quick off the mark releasing what was described as a summary brief containing analysis by the Department of the just announced Opposition policy. However when the issue arose in Senate Estimates hearings of what other advice she had received, in addition to the two pages released, it emerged there was plenty more, but don't expect to see it until the Government is good and ready, or maybe in open access records in 20- 30 years.  Here is the thrust of the discussion( Finance and Public Administration 08/02/2010 F&PA 118):

Senator BIRMINGHAM—What type of other analysis do we have? Is there a detailed brief that goes behind this summary brief?
Senator Wong—Quite a lot of advice has been provided to me.
Senator BIRMINGHAM—Has other advice on the coalition policy been provided by the department to you?
Senator Wong—Yes.
Senator BIRMINGHAM—Is that advice in the nature of costings or estimates? What type of advice exists?
Senator Wong—It is a range of advice.
Senator BIRMINGHAM—Why won’t you release that advice and government costings of the coalition’s policy?
Senator Wong—I have released a summary, which is on the public record. As I recall, you and your colleagues were critical of me having released that.
Senator BIRMINGHAM—Would you describe the government analysis of the opposition policy as somehow being commercial-in-confidence?
Senator Wong—No.
Senator BIRMINGHAM—Can you give a particular reason as to why it would not be released?
Senator Wong—I have not released it.
Senator BIRMINGHAM—Why have you not released it?
Senator Wong—Because I have not released it. We have released a summary of the analysis.
Senator BIRMINGHAM—You do not understand the word ‘why’?

Senator Wong—Not every piece of advice that goes to government is released by government. You know that.
Senator BIRMINGHAM—With all due respect, this is not advice on government policy; this is advice on opposition policy. You seem to find it convenient to release a two-page summary brief, with a table attached.

The Minister subsequently said she would take the question of more disclosure on notice.

Last year then Clerk of the Senate Harry Evans made this comment after an Estimates round:

"On at least eight occasions ministers and officers invoked the claimed principle that advice to government is not disclosed. This is demonstrably false, as it is contradicted by all the occasions on which such advice has been disclosed....... What seems to be really meant by these statements is that advice is disclosed when the government chooses to do so."