"Shield laws" for journalists

are under debate again in this little part of the world. The Opposition put up a bill which passed the state's Legislative Assembly but then failed to get through the House of Representatives. It leaves us out of step with most of the country.
The Attorney-General has declared the laws "unnecessary" and claimed that a journalist has never been imprisoned for failing to reveal their sources. That is incorrect - at least one journalist has spent time incarcerated for refusing to name a source.
At Federal level there is an attempt to bring in other laws which would possibly see a journalist imprisoned for revealing matters of national security. There the Federal Attorney-General has said that the laws are not aimed at journalists, rather they are aimed at terrorists and those supporting them.
Both situations have journalists and others concerned. They have me concerned.
I think we need shield laws. I also think they should not apply to behaviour which is irresponsible.
There are things journalists uncover - or, more likely, get told - that should be made known. It will genuinely be "in the public interest" to inform people about something which has happened or is currently happening. The recent information about the highly inflated water bills in this state is one of those stories which needed to be aired.
It is plain the government is using many household bills to try and raise the money to run a state which is as good as bankrupt. People need to know that. They may not be able to do anything about it but at least they will know why their bills are so high. (Even if there is a change of government at the next election it will change nothing because a government would need the money.)
It is also improper for a journalist to reveal issues of national security which put people at risk. If a journalist were, for example, to name "undercover" agents who had befriended terrorists in order to gather information and prevent an attack on innocent people then surely that is wrong. The journalist would in effect be assisting the terrorists and endangering the lives of others.
I know people who say "but no responsible journalist would do that". Perhaps not but there are irresponsible journalists - and even the most responsible journalists would find it hard to resist a really big story. They would attempt to justify it.
One of our local columnists wrote an article in the state newspaper earlier this week. It sounded good but it was incorrect. It gave entirely the wrong impression of a social programme that she happens not to personally like. On being challenged she has allegedly claimed that this is what she was "told", that complaints were made and she believed them to be true. A balanced story would have involved more research and some acknowledgment of the actual facts - but then it is unlikely the paper would have found the space to print it.
We need to balance the right to know against the right to privacy and the right to safety. We need to balance the right to offer an opinion with the right to accurate information.
If journalists do not behave in a responsible manner then they should not be shielded. The problem is that any irresponsibility on their part may end up denying all of us information we need to make an informed decision for ourselves.
If someone has an answer to this could they please let me know?