But now to the other big political story of the week:

DOUGAL BEATTY: It was around 4.30 this afternoon when plain-clothed AFP officers moved in on the Australian Workers' Union here in West Melbourne. We understand that this is a co-ordinated raid by Federal Police, they also targeted the union's building up in Sydney. Now we're yet to see the officers emerge with any kind of evidence, they're in the building as we speak. — Nine News Melbourne, 24 October, 2017

Now we have those dramatic pictures because when police arrived at the Melbourne HQ of Bill Shorten's old union last Tuesday the media was waiting for them.

And as police piled into the AWU's Sydney office the cameras were there as well, with Seven's Chris Reason one of several TV reporters on the spot:

CHRIS REASON: ... on behalf of the ROC, the Registered Organisations Commission. It happened about 4.30 this afternoon. Eight to 10 police officers marched in here, the media had been given a tip-off. We were here waiting for them. — Seven News Sydney, 24 October, 2017

Ten News was also there as the raids unfolded, with the drama perfectly timed for a live cross to the 5 o'clock bulletin.

ANDREW DENNEY: That's right Sandra, only a few moments ago, around a dozen officers from the Australian Federal Police arrived here at the headquarters of the Australian Workers' Union. They were armed with a search warrant and are currently going through financial documents upstairs. — Ten News Sydney, 24 October, 2017

The ABC did not arrive until after the police, but one of its Canberra reporters had the story online within three minutes of the raid.

And next day on Sky, former NSW Labor premier Kristina Kenneally stated the obvious:

KRISTINA KENEALLY: That didn't just happen. That came from somewhere. That was a political act to tip off the media. — Sky News, To The Point, 25 October, 2017

And before long, Labor was pointing the finger at Employment Minister Michaelia Cash, whose initial request had prompted the AWU investigation:

Cash's office 'tipped off media' — The Australian, 25 October, 2017

Cash denied it in a hurried meeting with the Prime Minister. And then fronted up to Senate Estimates to deny it again, five times in all, before adding:

MICHAELIA CASH: ... and quite frankly I am offended on behalf of my staff as to those allegations. They are very serious allegations. — Senate Estimates, 25 October, 2017

And that's where it would have rested had BuzzFeed's young political correspondent Alice Workman not spoiled the party:

BuzzFeed News has spoken to journalists who claim they received a phone call from Cash's office an hour before the raids, to make sure there would be cameras outside the AWU offices in Melbourne and Sydney. — BuzzFeed, 25 October, 2017

And with that revelation forcing Cash to tell the Senate she had known nothing, BuzzFeed's headline soon got this update:

And a staffer has now resigned — BuzzFeed, 25 October, 2017

For seven hours, the Senator's staffer had watched his boss mislead parliament, but said nothing.

So too had several in the media, who knew full well it was Cash's office that had given them the tip.

So, should they have revealed it?

The Daily Telegraph's national political editor Sharri Markson - the recipient of many a government leak - had no doubt the answer was no:

Shocking night for the media. Some journos clearly do not know how to protect sources. — Twitter, @SharriMarkson, 25 October, 2017

And two other senior News Corp journalists backed her up, with

Herald Sun chief of staff Paul Tatnell tweeting about betrayal.

And The Advertiser's Andrew Hough adding:

If I was journo who revealed source I would feel ashamed & should resign from my profession. Utter disgrace ... — Twitter, @andrew_hough, 25 October, 2017

And before long, on Twitter, battle was raging, with former Fairfax journalist Margo Kingston replying just as forcefully:

bloody hell, you think a photo op tip off deserves protecting a lie to Parliament? WOW. — Twitter, @margokingston1, 25 October, 2017

And The Guardian's Amy Remeikis offering a similar riposte to Markson:

Sorry - but that's bullshit. Once the minister misled the committee, it was public interest — Twitter, @AmyRemeikis, 25 October, 2017

With battle dividing on political lines, Peter Dutton and Ray Hadley agreed in their weekly radio chat how shocking it was the leaker had been outed.

But it was not only the government or its supporters arguing that journalists must protect sources at all costs, with Seven's Robert Ovadia writing on Yahoo7:

... there is no circumstance ever that justifies a journalist revealing their source, beyond preventing imminent criminality or protecting people's safety. — Yahoo7, 27 October, 2017

Well, we humbly beg to disagree.

A lie was being told to Parliament and some in the media knew it to be so.

What's more the leak was hardly whistleblowing. It was what the media call a drop.

And as Imre Salusinszky, press secretary to former NSW premier Mike Baird, recently explained:

A drop is neither more nor less than a confidential transaction between a government official and a third party, designed to benefit both. One gets an exclusive story that draws an audience, the other gets favourable news coverage. — The Sydney Morning Herald, 2 September, 2017

Drops can also be political dirty tricks. And this looks remarkably like one.

Because the police were raiding the AWU on the orders of a new government body, the Registered Organisations Commission.

And its first big investigation had been requested by none other than Senator Cash.

And even Andrew Bolt - who's no fan of the unions or of Labor - thought this looked a bit off:

ANDREW BOLT: This commission was in fact set up by the government. It was in fact investigating Shorten on a referral from the government. And that makes this all look suss. — Sky News, The Bolt Report, 25 October, 2017

The offence the commission is investigating is 11 years old and carries a mere $4000 fine.

And the potential crime? That Bill Shorten's old union gave $100,000 to GetUp, an organisation that shares many of its aims, and may not have properly documented the donation.

Once again, even Andrew Bolt finds that a concern:

ANDREW BOLT: I have to say, this now seems part of a disturbing pattern, of the Liberals under both Tony Abbott and Malcolm Turnbull, to use state power against a political enemy. — Sky News, The Bolt Report, 25 October, 2017

So, with that as background, and with a minister misleading Parliament, is it really the media's duty to stay silent?

The Guardian's Katharine Murphy thinks not:

This was not a cabinet leak, or someone blowing the whistle, or somebody telling you something in the public interest that someone else really doesn't want written - this was a person saying get a camera down to the AWU offices in Sydney in Melbourne ... that he clearly believed would serve the government's interests. — Facebook, Katherine Murphy, 27 October, 2017

And Sky's Samantha Maiden agreed:

... staffer is not exactly a whistleblower. Why should journos participate in a cover up? — Twitter, @samanthamaiden, 25 October, 2017

Maiden said later on Sky that she would not have outed her source but would have urged him to correct the record.

But today a number of senior press gallery journalists - Chris Uhlmann, Dennis Shanahan and Mark Riley among others - have taken the traditional line in The Australian, with Riley also telling ABC's Insiders:

MARK RILEY: You can put bamboo under my fingernails, I will never, ever cough a source. — ABC, Insiders, 29 October, 2017

Luckily, it's not likely Riley will ever be put to that test.

But is it the system or the public interest that journalists are trying to protect here?

A couple of days ago, the Telegraph was berating critics who said it should not report on Barnaby Joyce's personal life, claiming:

... politicians (and, indeed, certain members of the Canberra press gallery) believe the gallery's role is not to report but to conceal. — The Daily Telegraph, 24 October, 2017

And adding:

... the Canberra club believe this should remain in-house and not reach the broader public. — The Daily Telegraph, 24 October, 2017

But surely with this story there was a far greater right to know.

It was about dirty politics, media manipulation and misleading Parliament.

And we believe there was a duty to the public to disclose the involvement of the minister's office.

And it's worth noting it was BuzzFeed, a relatively new member of the Canberra press gallery, that broke the story.