Matthew Niall has always seen himself as Australian to the core, but he recently found out a decision to get an Irish passport more than 20 years ago led to him being stripped of his Australian citizenship.
On New Year's Eve on the cusp of 2022, the Department of Home Affairs sent the 41-year-old an email that left him reeling.
It said it did not believe Mr Niall was an Australian citizen at all — and that he hadn't been for the past two decades.
That's despite voting in elections, travelling on his Australian passport, and getting Australian citizenship for his son in 2008.
It was because of a little-known law that saw adult Australians who got a second citizenship automatically lose their Australian citizenship.
The issue of lost citizenship could potentially affect thousands of people who may not even realise it, and it often only comes to the department's notice when they apply for citizenship for their children.
Mr Niall, who was 19 when he got his Irish citizenship and passport, said he was blindsided and had no idea about the automatic loss of his Australian rights.
"It was devastating. It was horrible," he said.
"I couldn't believe it … This is some sort of mistake.
"If I'd known about this legislation, I never would have done it … It just felt like a nightmare."
It's now had distressing consequences for him and his family.
How did it go unnoticed for 20 years?
Mr Niall was born in Sydney and lived in Australia for the first 21 years of his life.
He had what he describes as a typically Australian childhood, full of weekends spent at the beach, which fostered a love of the outdoors and an adventurous spirit.
In part to connect with his grandfather's Irish heritage, he applied for Irish foreign births registration and was granted his second citizenship in September 2001.
His Irish passport would later help Mr Niall travel and work in Europe.
Currently living in Copenhagen, Mr Niall said he always hoped to return to Australia, but circumstances kept him in Europe for the past two decades.
In his early 20s, he met a woman in Denmark and they had a son together, Alexander, who is now 16.
When the relationship ended, he chose to stay in the European nation to remain close to his son.
"He's my son. I couldn't leave him, I didn't want to leave him," he said.
He later met a Swedish woman, Louise, and they now have two daughters, Ellie and Norah, aged three and one.
In late 2021, as pandemic border restrictions eased, he and Louise began taking steps to travel to Sydney, which included acquiring Australian passports for their young daughters.
But at that juncture, the Department of Home Affairs told him he had lost his citizenship.
Under section 17 of the 1948 Citizenship Act, an Australian citizen over the age of 18 who takes up a second citizenship "shall, upon that acquisition, cease to be an Australian citizen".
That section previously required a person to be outside Australia when they acquired their second nationality, but it was amended in 1984 to include adults who got a second citizenship from within Australia, as Mr Niall did.
On April 4, 2002, about six months after Mr Niall got his Irish passport, that section of the law was repealed.
But it didn't work retroactively or reinstate lost citizenships, leaving Mr Niall and his children in a quagmire.
He was given a window to prove he had not ceased to be a citizen and he requested time extensions to gather paperwork, which were initially granted, but in June last year, his citizenship was revoked.
With that, his passport was rendered invalid. He was no longer eligible for consular services overseas, and he lost his right to vote and his right of visa-free entry into Australia.
After scrambling to get Swedish passports for his daughters, the young family was eventually able to visit Sydney last year — before his passport was cancelled — but not without hassle and his parents lobbying their local politician about their son's situation.
People who have lost their citizenship under this outdated law can apply to resume their citizenship, a process that carries a fee of $210 and requires a person to show they are of "good character".
The processing takes an undisclosed amount of time.
The Nialls said they had spent hundreds of hours and thousands of dollars on a migration lawyer to try to resolve the issue.
There are also consequences for Mr Niall's children. They can no longer get Australian citizenship by descent because Mr Niall was not technically a citizen at the time of their births.
Instead, they must apply for citizenship by conferral, which the minister must approve or refuse.
From their home in North Sydney, Mr Niall's parents, Roz and Christopher, said it was inconceivable that their son was not Australian, and they said the ordeal had taken a toll.
"It's ridiculous. It's unbelievable really," his mother said.
She said her husband had been conscripted into the Australian Army during the Vietnam War, and that two of Matthew's grandparents had served in World War II and sustained lifelong injuries.
"My father was a Rat of Tobruk. Chris's mum was a nurse in the army," she said.
"I don't think we could be more Australian."
Is it legal to remove citizenship?
Kim Rubenstein, a legal scholar at the University of Canberra, said there was an underlying question about whether the automatic loss of citizenship was lawful, but had never been tested in court.
"The stripping and loss of citizenship is dramatic," she said.
"It has significant consequences on people's lives.
"People understand this is a very unfair consequence, and one that should really be remedied."
North Sydney independent federal MP Kylea Tink has written a letter to the minister of Home Affairs about his case.
"The thing here that I find extraordinary is that we have a citizen who was able to revoke their citizenship accidentally," she said.
"Surely if you're in a situation where you are about to sign away your citizenship, that should be something that should be coming up in big flashing lights."
She is calling on the government to find a compassionate solution.
"I think it's bureaucracy gone mad. It doesn't have to be like this. Just because computer says no, doesn't mean that human intervention can't step over and go, 'But this is what's right'."
Professor Rubenstein said there could be a legislative fix.
"The most straightforward way would be for parliament to remedy the scenario and to recognise that people who may have ... lost their citizenships, to be reinstated as if it had never been lost," she said.
But there was also an opportunity to challenge the original legislation as unconstitutional — although it could be costly.
"I think there would be an argument to say that the automation of someone's loss of citizenship has a punishing effect on an individual, even if that wasn't the intention of the legislature," she said.
The Nialls are considering that approach.
"It's been unrelenting stress [and] trauma for a year, and I feel the way my son and his family has been treated is really, really wrong. I don't want that to happen to other people," Mrs Niall said.
Thousands affected before law change
In April 2002, section 17 of the citizenship act was repealed.
The minister for Citizenship and Multicultural Affairs at the time, Gary Hardgrave, heralded the change in legislation in a press release.
"This provision of the legislation was outdated, particularly given the large number of Australians overseas and the reality of global labour markets," he said at the time.
"Around 600–700 people come to the notice of my department each year as having lost Australian citizenship when they become citizens of another country."
The change was made "so that adult Australian citizens in future do not lose their Australian citizenship on acquisition of another citizenship".
However, the change did not benefit Australians who had already lost their citizenship under the old law.
In a statement, the Department of Home Affairs said there was no ministerial intervention power in relation to citizenship losses under section 17, but that people who lost their citizenship could apply to resume it.
Home Affairs Minister Clare O'Neil and Minister for Immigration, Citizenship and Multicultural Affairs Andrew Giles declined to comment to the ABC.
But in a letter to Ms Tink, Mr Giles said it was not possible to "reinstate" citizenship, only to "resume" it.
"A person who is approved for resumption of Australian citizenship becomes an Australian citizen on the day they are approved to become an Australian citizen again; it does not apply retrospectively to the date they lost Australian citizenship," he wrote.
"Due to the automatic nature of section 17 of the 1948 Act, where no application to the Australian Government was necessary and no decision was involved, losing one's citizenship can, understandably, cause a great deal of shock and distress."
Mr Giles wrote that often the department was left "unaware of the loss" of citizenship.
"It may not come to light until a later interaction with the department, if at all," he wrote.
Mr Giles added that Mr Niall may return to Australia, but if he was not a citizen at the time of travel, he would need to apply for a visa to enter the country.
Despite thousands being affected before the repeal, it remains unclear how many people have been told they're not citizens since 2002.
Due to variations in how citizenship losses have been recorded over time, the Department of Home Affairs does not have an existing data set on the total number of people who have been notified that they lost their citizenship under section 17 since 2002.
The department said it was not possible to estimate how many living Australian citizens lost their Australian citizenship prior to April 2002.
Mr Niall said the issue had not come up in 2008 when he acquired Australian citizenship for his son, who had always called himself half-Australian, but has now had his passport revoked too.
"My son has lost his citizenship. He's obviously devastated about that ... That was a difficult conversation," Mr Niall said.
Mr Niall is speaking out and has started a petition because he fears there may be many others unknowingly affected.
"This whole situation, it is absurd," he said.
"There hasn't been an appetite to make the change within the federal legislation or within parliament.
"I'd like them to step up and fix this. I don't want anyone else to have to go through what I've been through."
He said it felt like an intrinsic part of his identity had been taken away.
The thought of needing a visa to enter a country he has always called home also worries him, and he fears not being able to get to Australia quickly in the event of a family emergency.
"I'm terrified that something's going to happen to my parents. They're getting a bit older now," he said.
"Having lived overseas, I don't feel any less Australian.
"I feel exactly the same in terms of how I feel about my country, my upbringing — all those values that I got from growing up in Australia, I still have, and I pass them on to my children."
Editor's note: A previous version of this story stated that Australian adults who acquired a second passport between 1948 and 2002 automatically lost their citizenship. The article has been corrected to clarify it was the acquisition of a second citizenship, not a passport alone, that triggered the forfeiture of Australian citizenship.
The article has also been updated to clarify that between 1948 and 1984, section 17 referred to Australian adults who acquired a second citizenship while outside Australia. In November 1984, it was amended to remove the requirement to be outside of Australia.
