The number of current MPs and senators with questions around their status as dual citizens continues to rise, with independent Senator Jacqui Lambie revealing her father was born in Scotland. Since the original Citizenship Seven were sent to the High Court, Senator Stephen Parry has resigned, and Liberal MP John Alexander is looking into his family history. Then there’s the Labor MPs and senators who are also facing scrutiny about the exact dates they renounced their dual citizenship. 

So are dual citizens a particular affliction of the 45th parliament? Barnaby Joyce was first elected in 2005 — he’d been around for 12 years before realising that he was a Kiwi and therefore not eligible to sit in parliament. It is unlikely that Joyce and his dual-citizen colleagues are the first ones to read over the Australian Electoral Commission declaration, assume they are fine, and sign on the dotted line and go on to be elected.

Are former ministers squirming uncomfortably in their seats watching as this plays out? What happens then, to former MPs and senators who were dual citizens when they were in parliament but have since retired from the halls of power? Basically nothing, it turns out.

Questions have been asked about whether decisions made by Joyce and Fiona Nash, as ministers, could be challenged in the High Court. Constitutional expert Anne Twomey has written for The Conversation about the hurdles that would face potential legal challenges to Nash and Joyce on this question:

“It is most unlikely that any challenge to a law on the basis of votes in parliament by disqualified members would succeed in the courts.

“There is a greater risk that a challenge to a ministerial decision, made by a disqualified MP when he or she did not validly hold a ministerial office, could be successfully challenged.”

So if someone were considering leveraging the family tree of a former minister who made decisions they didn’t like, they are very unlikely to be successful.

Firstly, because decisions made by votes in parliament are unlikely to be interfered with by the court. So we are left with decisions only made by a minister.

Decisions made by Joyce and Nash before being referred to the High Court would be subject to the “de facto officer” doctrine, Twomey says, which means that the validity of decisions made by someone in a position of authority is protected, even if they are later found not to have validly held that authority. This would also apply to any former ministers who were dual citizens.

Twomey told Crikey “decisions are protected to protect the people who rely on those decisions, not those who make the decisions”.

“The courts are going to be very reluctant to unpick decisions that people have relied upon in good faith.”