Ask a person in the street how they know politicians are lying and, more likely than not, they’ll reply: “Because their lips are moving”.

Unfair? Sure. Politicians are mostly honourable people. So journalists have to take a more nuanced approach; we report that politicians “mis-speak”, they “over-promise” or, in Winston Churchill’s words, use “terminological inexactitudes”. Now, journalists are being called out on these overly generous circumlocutions. If it’s a lie, social media demands it be called one.

The “lie” debate recently exploded in the US after a tweet from The New York Times’ political correspondent Maggie Haberman: “Trump told two demonstrable falsehoods this AM …”

Twitter blew up (you’ll find some of the most interesting and funniest responses here). Haberman’s language was lampooned, and a debate followed about the weight and importance of the word “lie”.

Although Australia hasn’t (yet) had a political leader with the Trumpian propensity for “demonstrable falsehoods”, public attitudes to Australian politicians as a group are no more favourable. The to-and-fro would be familiar to anyone who’s spent any time on #auspol during the long-running Barnaby Joyce saga. Government ministers are returning fire too, alleging “falsehood” at the ABC in a variation of the Trumpian “fake news” attack on the media.

Politicians play on this, happy to take some short-term political gain for their party in exchange for the long-term reputational damage to the political class. Catchphrases like “Ju-liar” and “Unbelieva-Bill” are workshopped through social media for cheap laughs.

But in journalism, there’s something too definitive about “lie” when many of the statements of politicians more likely fall somewhere on that long continuum between absolute truth and out-and-out lie.

Take pre-election promises: “There will be no carbon tax under a government I lead” or “No cuts to education, no cuts to health, no change to pensions, no change to the GST and no cuts to the ABC or SBS”. Determining where statements like these fall on the truth-lie continuum depends on an understanding of context, understanding how the commitment aligns with other promises (implementing an ETS, achieving budget surplus) and an analysis of the concrete political situation.

The media highlights the contradiction between pre- and post-election statements, but their real job is to bring contextual understanding. Calling them “a lie” means knowing the unknowable: was there a deliberate intent to mislead? That’s a matter of political judgement, not journalism. It might put the press gallery out of step with #auspol, but that’s journalism.

Journalists can also get it wrong in their over enthusiastic embrace of Gotcha! moments, when political predictions turn out to be fundamentally mistaken. Of course, who can’t enjoy replays of: “And the High Court will so hold” or “rolled gold guarantee”?  Or the old perennial — shared across the parties — of gilded budget forecasts?

They’re a bit too easy; a substitute for proper context and in the online world, #auspol does it better than the #MSM can.

In politics, the greatest lies come masqueraded as truths, with politicians playing definitional games to suggest just about everything is a shade of grey. Most famously, Clinton: “I did not have sexual relations with that woman”, relying on a 16-year-old’s definition of “sexual relations”. Or, in the current, Australian context: when does a partner become a Partner?

When politicians play these definitional games, journalists can fall back on the “he said, she said” gambit, with all its limitations and flaws. Now, there’s an added problem: the cry of “fake news” has become the go-to defensive play, a cry that is all about undermining public confidence in the media. One of the many lessons from the Trump experience, is that politicians can weaponise their political support against journalism. The monthly complaints to the ABC are about undermining its credibility with the party base and bullying it into a more compliant attitude.

Unfortunately, the media lacks the public trust to resist. The ABC has more trust than most, but as the budget cuts show is also more directly vulnerable. And that’s before we get to Australian defamation laws.

We’re going to have to leave the “lies” to the political argy-bargy, with journalists stuck with calling out “terminological inexactitudes” as “demonstrable falsehoods”.