Federal parliament’s dual citizenship spotlight was thrown onto the Labor opposition on Tuesday as a defiant Katy Gallagher was forced to deny she had ever held Ecuadorean citizenship.

One Ecuadorean citizenship expert backed her claims after News Corp reported that the former ACT chief minister had held dual citizenship through her Ecuadorean-born British mother.

Under Ecuador’s current constitution, “persons born abroad of a mother or father born in Ecuador and their descendants up to the third degree of consanguinity” are “Ecuadorians by birth”.

In a statement released on Tuesday morning, Senator Gallagher argued that it did not apply to her situation.

“The 2008 Constitution was not in effect when my mother was born in 1943,” she said.

Ecuadorean academic Gabriel Echeverría, an expert in citizenship, told The New Daily the 2008 Constitution was “retrospective”, meaning the new laws would apply to Senator Gallagher.

But Mr Echeverría, who authored a report on the country’s citizenship laws in February, said that while Senator Gallagher had “the right to claim Ecuadorian citizenship … the process is not automatic”.

“The only valid Constitution is the current, the old ones are important only for their historic value,” he told The New Daily.

“The point, though, is that for both born and children of Ecuadorians born abroad the Constitution establishes ‘the right for them to be citizens’, which does not mean they are citizens.

“They have, if they want, to ask and fulfil the procedures in order to become citizens.”

That meant “asking for Ecuadorean citizenship at the Ecuadorean Embassy and following the bureaucratic procedures”.

Ecuadorean immigration lawyer Sara Chaca agreed, telling The New Daily a person in Senator Gallagher’s situation would “have to apply” for citizenship.

Constitutional law experts in Australia said Senator Gallagher’s official case appeared to be complex.

“The High Court has said whether you are a subject or citizen depends on the law of another country,” University of New South Wales Professor George Williams told The New Daily.

“The key question here is does Ecuador regard Katy Gallagher as a citizen.”

Earlier in the month, Deputy PM Barnaby Joyce referred himself to the High Court over his New Zealand citizenship. He had received it through his New Zealand-born father and as a result of a 1948 law change that came into effect after his father was born.

Mr Joyce’s case, along with fellow Nationals Matt Canavan and Fiona Nash, and crossbenchers Nick Xenophon and Malcolm Roberts, will be heard by the High Court in October.

The Ecuadorean constitution changed many times throughout the 20th century as the country faced political turbulence and new leaders tried to cement their authority.

Under article 12 of the country’s 1928 constitution – which was in place when Senator Gallagher’s British mother, Elizabeth Mary Gallagher, was born in Ecuador – appears to suggest any person born in the country was considered Ecuadorean.

The 1967 constitution – which came into effect three years before Senator Gallagher was born in Australia in 1970 – also included provisions for a person born overseas to become Ecuadorean by birth through Ecuadorean parents.

Senator Gallagher was born in 1970 and entered Parliament as a senator for the ACT in 2015.

She said on Tuesday: “As part of the ALP vetting process, I disclosed that my mother was a British citizen, born in Ecuador to British parents, who were temporarily working in Ecuador.

“The circumstances of my mother’s birth and citizenship were investigated.

“As a result of these investigations it was determined that I had not obtained Ecuadorian citizenship by descent from my mother.

“I am not and have never been an Ecuadorian citizen.”

The New Daily sent questions to Senator Gallagher’s office but did not receive a response.