There has not been this much excitement and interest in the constitution since that seminal example of Australian film, The Castle, was released in 1997.

First it was two Greens senators, then a Nationals Minister, then One Nation joined the malaise.

Deputy Prime Minister Barnaby Joyce added his name to the list and just as the latest Parliamentary fortnight was coming to a close, Mr Joyce's deputy, Fiona Nash, announced she was referring herself to the High Court over the possibility of her being a British citizen.

But as this seemingly unprecedented citizenship drama sweeps through federal Parliament, there is a need to stop and think about just how the High Court could act in figuring out who can and cannot be a politician.

Section 44(i) of the nation's founding document disqualifies someone from office if that person:

…is under any acknowledgment of allegiance, obedience, or adherence to a foreign power, or is a subject or a citizen or entitled to the rights or privileges of a subject or a citizen of a foreign power…

The grey area there is the word "entitled".

Does it mean an individual has to actually be a citizen or another country, or just be entitled to claim citizenship in the future?

We now have a Long White Cloud hanging over Barnaby Joyce, and whether he could be a New Zealand citizen. As far as the Kiwis are concerned he is one of them.

Mr Joyce's father was born in New Zealand, and emigrated to Australia before the concept of Australian or New Zealand citizenship even existed.

It was not until the late 1940s that Aussies and Kiwis were considered anything other than British subjects.

Under New Zealand law a child born to a New Zealand citizen is automatically given Kiwi citizenship, and it does not have to be activated or registered.

That is where the uncertainty arises. Barnaby Joyce argued he never sought it out.

Could acquiescence amount to citizenship? Malcolm Turnbull, George Brandis and even the ABC's election analyst don't believe it does.

Another example is the brief kerfuffle over Victorian Liberal MP Julia Banks a few weeks back.

Like many Australians, including yours truly, she is the child of migrants.

Ms Banks' dad was born in Greece, and became an Australian citizen before she was born. She argues she has never held Greek citizenship.

But there is little doubt that by descent she could claim it.

Does that mean she is "entitled" to foreign citizenship, and therefore disqualified under the constitution?

Ms Banks and the Liberal Party issued a statement saying she had never held or sought Greek citizenship.

Justices of the High Court are, by nature of their appointment, some of the wisest legal minds in the land. So supposing how they may rule is fraught.

But if the High Court was to start saying everyone entitled to foreign citizenship was ineligible, it would wipe out a swathe of our MPs and senators who have never tried to claim allegiance to any other county.

Surely the Court would have to take into account the practical effect of making that judgment, and the ensuing chaos it would cause.

Case law too suggests the need to act on any eligibility.

The people who drafted the nation's constitution more than a century ago were (and yes, this is stereotyping) were generally old white men who would at the time have been counted as British subjects.

They too would find themselves kicked out of Parliament if such an interpretation had needed to be adopted back then.

Of course, the High Court could take a strict interpretation and say that eligibility for foreign citizenship is enough to disqualify an individual.

But that would not stop prospective parliamentarians from trying to liberate themselves from any future claim on citizenship.

Former Labor MP Alannah MacTiernan did just that in renouncing her inherited Irish citizenship, saying she also surrendered any potential entitlement in the future.

So the High Court will be asked to decide exactly what "the vibe" of the Constitution is actually meant to be.