If it was not clear before, the situation of Deputy Prime Minister Barnaby Joyce must now have made it obvious to the Turnbull government that, if it survives, it will have to begin the process of amending the constitution's provisions on the eligibility of MPs.

Constitutional reform is not something any federal government these days views with much enthusiasm. Failure is highly likely. To pass, a referendum must gain a majority of votes, plus a majority in more than half the states. That sets the bar so high that any serious campaign against a proposal will see it fail. And oppositions are often willing to campaign against proposals they actually agree with just to frustrate the government of the day.

Even so, it would be churlish in the extreme for this opposition to campaign against reform when recent history has shown it is so obviously necessary.

Four MPs – three senators and now one member of the lower house – have either admitted they have breached section 44(i), or have asked for an adjudication of their status. The section bars citizens of other countries from parliament. (Other subsections, to do with pecuniary interests or offices of profit under the Crown, have also caused other senators difficulties.)

The basic principle of section 44(i) – that MPs should be Australian citizens, not citizens of any other country – is sound. Some may argue that in this multicultural age of increasing globalisation, dual citizenship is becoming more and more common, and our parliament should accept, and reflect, the trend. That view is flawed. Australian voters naturally expect their parliamentary representatives to be from this country and to represent its, and their, interests, not those of any other country.

It is precisely because of globalisation and the ease with which influence can be peddled from outside that the eligibility rules need to be tight.

Parliament's Legal and Constitutional Affairs Committee examined the issue in 1998 and, recognising its complexity in the modern world, recommended the subsection be replaced with a basic requirement that MPs be Australian citizens, and that the constitution empower Parliament to decide what grounds in relation to foreign allegiance would disqualify MPs from office.

It sounds like common sense. Can a referendum succeed which enacts it?