Spot the difference: senior Nationals figures discover they might be dual citizens and thus ineligible to stand for election to Parliament. One knows there are journalists ready to publish a story about them; the other knows their secret is safe for now. Guess which one goes straight into Parliament last Monday and ‘fesses up, and which stays silent until the Senate was packing up last night, after the commercial news bulletins are over.

The Attorney-General spent this morning explaining why it took four working days for the government to come clean about Deputy Nationals Leader Fiona Nash, involving convoluted explanations of British barristers, a busy Solicitor-General, legal advice and meetings with the Prime Minister.

[Hinch’s Senate Diary: why the citizenship debacle is all my fault]

How convenient that, in a week in which the government devoted itself to an elaborate conspiracy theory about trans-Tasman skulduggery against Barnaby Joyce, one that succeeded in offending even conservative allies in New Zealand, it was staying shtum about how Joyce’s deputy, too, was a foreigner. Perhaps Julie Bishop was trying to work out if she could somehow blame Jeremy Corbyn. But, of course, it would have made the Great Aotearoa Conspiracy looking even sillier, if that, somehow, were possible. In contrast, Nick Xenophon this morning revealed he had started trying to establish whether his Cypriot background had afforded him British citizenship. The contrast in transparency is acute. 

The government’s tangled position on who stays and who goes for being a foreigner is now even more complicated. The government was happy to mock Greens senators Ludlam and Waters for failing to ensure they weren’t dual citizens, with Barnaby Joyce lecturing them about black-letter law. Then Matt Canavan is busted, but he only quits cabinet and voting in the Senate. Then Joyce is outed, but nothing happens at all, except to get upbraided in Parliament by the Prime Minister for his now inconvenient statements on black-letter law. Then Nash is pinged, but even though she could copy Canavan and step down without affecting the Senate numbers (Canavan is paired, as are Ludlam and Waters until replaced), because Joyce hasn’t stood down she can’t either because that would merely make Joyce’s position even less tenable.

[Greens shock: Scott Ludlam resigns over NZ citizenship]

This week has been a good demonstration of why doubling down on a misjudgement can be far worse than the embarrassment of retreating. Julie Bishop made a prize goose of herself and damaged relations with New Zealand, but she insisted on humiliating herself in Parliament. And instead of banishing Joyce until his case is sorted out, the government has brought further pain on itself trying to justify his retention. For Labor, Joyce will be a gift that keeps on giving, especially if he becomes acting prime minister while Turnbull is out of the country.

It’s still not too late to cut Joyce and Nash adrift until their fates are resolved. Even at this point, the cost of doing that is less than the pain the government — to the extent it’s actually doing any governing at the moment — is going to endure in coming weeks.