Two men born overseas, who were never Australian citizens and had no intention of ever becoming so - and who had committed violent crimes - went to the High Court claiming the government had no authority to expel them under the Migration Act 1958 because neither of them were aliens within the meaning of Section 51 (xix) of the Constitution.
Each man claimed they enjoyed special rights because their Aboriginal ancestry gave them a connection to the land, which meant they were not aliens and therefore could not be deported from Australia.
Only one of them persuaded the court of his ancestry, but that was enough.
A slim majority of the justices ruled recently that an Aboriginal person could not be an alien.
The High Court's decision was handed down at the same time as the anniversary of Kevin Rudd's 2008 Closing the Gap initiative.
The ruling provoked fiery debate about Aboriginality, the rights of Indigenous people, and, of course, the vexed issue of constitutional recognition.
But the central issue, lost in the heat of argument, is that of citizenship.
An "alien" is simply a person born outside Australia to non-Australian parents who has not become a citizen.
An alien who commits a violent crime can be deported.
And that makes sense to most of us: we want the state to protect us from violent criminals.
An alien who commits a serious crime forfeits any right to live in this country and mix in our community.
But by ruling that any person with Aboriginal ancestry cannot ever be an alien, the High Court has demolished the reasonable expectations of all right-thinking Australian citizens.
The court has created a new category of "non-citizen non-alien" who enjoys special protections - not just under the law but under the Australian Constitution.
Every new Australian citizen settling in this country makes a formal commitment to uphold the rights and responsibilities that go with being a citizen.
Enjoying equal protection and equal standing under the law is one of those important rights for all Australian citizens.
We look to Parliament to uphold those rights, and to protect us.
It is easy to see why the High Court decision has sparked furious debate.
The gap that Kevin Rudd sought to close still exists.
Indigenous people still suffer serious disadvantages in terms of health, education, and welfare outcomes.
And constitutional recognition of the special standing of Indigenous people is seen by many as a way to address historic wrongs.
Rights have been separated from citizenship and extended to those with no intention of becoming citizens. By detaching rights from citizenship and conferring them on non-citizens, the court has diminished what it means to be an Australian citizen ... unelected judges have also made a change to the Constitution.
But the court has provoked anger amongst critics because a majority of the justices have taken the concept of Aboriginality and discussed it in terms of another very specific, legal one: that of "alien".
Rights have been separated from citizenship and extended to those with no intention of becoming citizens.
By detaching rights from citizenship and conferring them on non-citizens, the court has diminished what it means to be an Australian citizen.
In addition to changing the meaning of citizenship, unelected judges have also made a change to the Constitution with its reinterpretation of section 51 (xix).
By altering what "alien" means in this way, the court has restricted exercise of the rule of law with no regard to the wishes of citizens who elected MPs to parliament to make laws in the first place.
In a liberal democracy, members of the community are held in common bonds of belonging known as "civil society".
But civil society is only as strong as the institutions - parliament, police, and courts - supporting those bonds.
We must be confident in those institutions because they are the guarantors of all the rights which are a privilege of citizenship.
By eroding citizenship and disregarding expectations of the community, the High Court's decision threatens both to weaken those crucial bonds of civil society and to divide our county along the lines of race.
Peter Kurti is director of the Culture, Prosperity & Civil Society program at the Centre for Independent Studies, and Adjunct Associate Professor of Law at the University of Notre Dame Australia.