Behind Malcolm Turnbull’s emotive press conference at which he castigated the “shocking error of judgement” of his deputy, Barnaby Joyce, in having an extra-marital affair, and the 1000-word complaint his office delivered to the ABC over a column by the ABC’s chief economics correspondent, Emma Alberici, is a dangerous tendency to overreact to criticism.

What’s more, it is un-prime ministerial. A leader should rise above the fray, or at least try. Too often Turnbull is duking it out with his enemies, real or imagined, rather than letting others do it for him.

Since he took over the prime ministership, the famously arrogant and bad-tempered Turnbull has tried to be more collaborative and consultative, recognising that his downfall as Opposition leader in 2009 could partly be blamed on his inability to suffer fools, and the deep well of hostility he’d built among frontbench colleagues.

However, Turnbull still has a strong line in vitriol. We got a glimpse of it in his preparedness to publicly humiliate Joyce on Thursday, saying the deputy PM had “appalled all of us”. Rightly or wrongly, he really dumped Joyce in it. Turnbull’s performance was raw, and clearly hit home. Some Nationals reckon there was more feeling in his denunciation of Joyce than we’ve seen in his attacks of Bill Shorten.

Often Turnbull’s attacks are most personal, and most forceful, when his position is weakest – in effect, when he’s been caught out. In this morning’s News Ltd tabloids, columnist Andrew Bolt writes that Turnbull had exposed himself to accusations of hypocrisy for covering up Joyce’s affair last year, certainly ahead of the New England by-election: “Turnbull won’t say when he knew it, and won’t explain what he told Joyce about it. One word from Joyce on what really happened could destroy Turnbull.” Bolt says one of them must go – he is unsure which – and indeed it seems Joyce’s leadership of the Nationals could be tested at next Monday’s partyroom meeting, with one potential rival, Michael McCormack, refusing to rule out a challenge.

If this is all going to plan for Turnbull, the plan is a very strange one. Turnbull might well vanquish Joyce, but he has lowered himself in the process, as today’s Newspoll figures suggest, with not just the two-party count but also Turnbull’s preferred PM rating plunging, despite voter support for the #bonkban and widespread disappointment in Joyce.

Likewise, without getting into the back-and-forth debate among economists about the merits of Emma Alberici’s comment piece on business tax, published last week, and since pulled down, it is disappointing as a journalist to read in this morning’s Australian [$] that the Prime Minister’s Office itself felt compelled to add its voice to that of the treasurer and the communications minister and send a critique to the ABC’s head of news, Gaven Morris.

The PMO’s reported criticisms in the complaint are arguable at best – for example, is the government really suggesting that Alberici lifted the word “giveaway” from a list of ALP talking points? She is that partisan? – and include unprovable smears like “Alberici has a habit of only including comments from people who agree with her”.

Turnbull has a few bad habits himself, including attacking ABC journalists and going over their head to the boss: in 2015, when he was communications minister mounting a campaign for the leadership and virtue-signalling to the hardliners on the Coalition’s backbench, it was Q&A in his sights over including the hapless Zaky Mallah in the audience; in 2013 it was then ABC journalist Nick Ross’s coverage of the Coalition’s NBN that drew his ire. Ahead of the 2013 election, Turnbull even complained that Alberici didn’t give him equal time in a debate on Lateline over NBN policy with the then minister, Anthony Albanese. It was rubbish: after a word count, it turned out Turnbull actually got more of a say than Albanese.

As Bernard Keane writes in Crikey today, it amounts to censorship. When combined with the anti-journalism workings of repressive laws to prevent foreign espionage, or impose data retention on telcos, it amounts to a sustained attack on free speech in which section 18C pales into insignificance. People have a right to be bigots, it seems, but not government critics. The PM should play the ball, not the journalist.

This article has been updated to reflect that, contrary to reporting in The Australian this morning, the critique was 1000 words rather than 6000 words.

since this morning

Fairfax Media is reporting that leadership pressure on Barnaby Joyce has escalated. In an awkward interview on Sky News, rival Michael McCormack repeatedly refused to rule out a challenge or pledge his support for the deputy prime minister. Announcing his gaming policy ahead of the South Australian election on March 17, SA Best leader Nick Xenophon said that over the next five years he wants to reduce poker machine numbers by half in hotels that currently have 10 or more, and cap each spin at $1, remove EFTPOS access near machines and ban political donations from the gambling industry. Nationals MP George Christensen has refused to apologise for posting a photo on Facebook of himself holding a handgun with the caption “You gotta ask yourself, do you feel lucky, greenie punks?” Prime Minister Malcolm Turnbull has described it as “clearly inappropriate”. in case you missed it

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