Bill Shorten rose in Federal Parliament on Thursday afternoon last week to give a rousing defence of the ABC. An hour later, an email arrived in ABC managing director Michelle Guthrie's office from Communications Minister Mitch Fifield.

"The Labor Opposition with me as leader will defend the independence of the ABC, and a Labor government with me as prime minister will defend the independence of the ABC", Mr Shorten told Parliament.

Senator Fifield, by comparison, wanted to complain.

The complaint? That several ABC journalists had retailed "the Labor lie" that the Government may have chosen the dates of five looming federal by-elections for political reasons.

Having now a very direct interest in the political debate about the ABC, I rang some people on both sides of politics to ask what had motivated the Shorten and Fifield interventions.

A Labor person said: "Well, there is the budget cut to the ABC, so that is worth talking about. But, people in regional Australia, for example north-west Tasmania, love the ABC, even if they don't like Labor. So it doesn't hurt to say we are on side."

North-west Tasmania, of course, is where the electorate of Braddon is located; where there is a by-election looming at the end of next month.

Asked why the Communications Minister should launch a complaint against not just political editor Andrew Probyn, and me, but Insiders host Barrie Cassidy and implicitly two Insiders panellists who don't even work for the ABC, Phil Coorey and Mark Kenny, the response from people inside the Coalition was equally pragmatic.

"You've got to play to the base."

In other words, for both sides, the ABC has moved from just being a perennial subject of political dissatisfaction, to an election issue in its own right.

Bill Shorten says he will defend the independence of the ABC. ( ABC News: Mark Moore )

The story under the surface

Like most stories in politics, there is always the story on the surface and lots more layers underneath.

Labor might believe in the editorial independence of the ABC. Mitch Fifield may be able to say that it is, technically, the Speaker of the House of Representatives who chooses the date of a by-election.

But that does not make underlying motives any less a part of the story.

An outcome of the lengthening years is that I have now been reporting federal politics from Canberra longer than any of the politicians who periodically occupy Parliament House.

So I know that attacks on the ABC come, perennially, from both sides of politics when they are in government.

That time frame — and the fact I have only been working at the ABC now for little over a month after 37 years working for Fairfax and News Corp — arms me to question occasions when partisan political attacks on the ABC might be dressed up as complaints about editorial standards.

The very complaints process by which the ABC operates — which for good reason obliges a level of response other media organisations do not apply to themselves — can too easily end up being used as a tool to bully the organisation and erode the trust of its audience.

Communications Minister Mitch Fifield has lodged his five complaints about the ABC in five months ( ABC News: Jed Cooper )

Reporting a political decision

Let's consider Senator Fifield's complaints.

Senator Fifield said it was, "totally unacceptable for the national broadcaster" to report "this Labor lie" that, "the selection of the date of July 28 was a political decision of the Government and the Prime Minister".

The Minister's reference to this as reporting a "Labor lie" lifts the first veil on the difference between someone complaining about a breach of editorial standards, and someone making a partisan attack.

Let's be blunt here. On the day the date of the by-elections was announced by House Speaker Tony Smith, senior cabinet ministers were joking with journalists about the fact the date would play havoc with Labor's planned national conference.

The Prime Minister's office — not the Speaker's office — was distributing data to show there was absolutely nothing out of the ordinary in waiting so long to hold a by-election.

Labor was, indeed, furious about the decision. But that doesn't make it a "Labor lie" to say, in an analysis piece, that the decision was a political one.

Timing is everything

No-one is suggesting the Speaker does not consult with the Government about the timing of the by-election.

It has been taken as a given since time immemorial that by-elections — like elections — were held at a time convenient to the government. Equally, it would be politically negligent on the Government's part if it did not make its views clear.

It is worth noting there has been no complaint from Mr Smith about the ABC coverage, nor from the Australian Electoral Commission.

It is also worth noting there has been no complaint to the Australian Financial Review which, in my case, published exactly the same column.

The particular irony of the complaint about my piece was that, the whole point of the article was to say that, while there were all sorts of versions of what had led to the decision, it ultimately was more important to look at the implications of the date, than the manoeuvres which led to it.

The apparently horrendous sins of the ABC — suggesting the Government might have an interest in the timing of five by-elections — should be seen in the context of a media environment in which some major commercial media are embarked on a relentless and quite open campaign to undermine the ABC because it is a threat to their commercial interests by competing across media platforms where they are struggling to make money.

Silent on other outlets

By contrast to Senator Fifield, who has now lodged his fifth complaint to the ABC in five months, the Government as a whole stays publicly silent about the antics of News Corp, even as ministers and their advisers privately moan about them.

From journalists who threaten to expose ministers as sexist for not giving them stories, to the sometimes-shrill campaigns run by News Corp papers against people and policies, the Coalition stays silent about the News agenda.

It feeds stories to the News Corp papers in the vain hope it will appease a beast which might otherwise turn against it, or in the deluded view the papers carry an influence in key electorates recent elections suggest is illusory.

There is plenty for anyone to be irritated about at the ABC, just as you can be irritated by the antics of News Corp.

The difference, however, is that the ABC still strives to deliver a diversity of information, analysis and opinion to its audiences.

Not everyone will always like the opinion, or the analysis. But if it is informed, and informative, it is doing its job.

News Corp has increasingly opted for a marketing strategy that appeals to a narrow political demographic, and one which suits the commercial interests of its owners.

If the ongoing attack on the ABC is indeed driven by market forces, it is time to consider the case that public broadcasting has never been more important as a public good.

Laura Tingle is 7.30's chief political correspondent.