Birthright citizenship explained as Trump's controversial order challenged in Supreme Court

Donald Trump has become the first sitting US president in known history to attend oral arguments at the Supreme Court, with ‘birthright citizenship’ being challenged in the chamber.

On Wednesday (1 April), the 79-year-old arrived at the court building on One First Street, Washington, DC, to hear a discussion on whether the United States should end its right to citizenship for anyone born in the country.

He left after listening to part of the hearing and returned to the White House, the BBC reported.

Currently, this citizenship status is automatically granted to any baby born to parents in the US, whether documented or not, as outlined in the Fourteenth Amendment.

“All persons born or naturalised in the United States, and subject to the jurisdiction thereof, are citizens of the United States and of the State wherein they reside,” the legislation reads.

Donald Trump attended Supreme Court to hear oral arguments regarding US citizenship today (Alex Wong/Getty Images)

However, following his return to the Oval Office on 20 January, Trump signed an Executive Order, titled ‘Protecting the meaning and value of American citizenship’, which sought to strip certain babies born in the United States of their birthright citizenship.

The Trump administration argued that ‘subject to the jurisdiction thereof’ featured in the Fourteenth Amendment meant that children of people not in the country permanently or lawfully were excluded.

It was therefore claimed that the new order would combat ‘significant threats to national security and public safety’.

Ahead of his arrival at the US Supreme Court, the Republican told reporters: “I'm going because I have listened to this argument for so long.”

If justices weighing the arguments lean more towards the administration’s favour and choose to uphold the executive order, then two cohorts of people will no longer be able to claim US citizenship at birth, as per the BBC.

These are children who are born in the country to undocumented immigrants, and those whose biological mother and father have temporary visas.

The oral arguments at the Supreme Court have already begun, with protests taking place outside of the building.

The citizenship of millions of Americans could be 'called into question', according to a lawyer (Getty Stock Image)

“It's almost unbelievable that we have to be here today,” said Democratic California Senator Alex Padilla.

The 53-year-old said that while the Fourteenth Amendment shouldn’t be up for debate, it’s likely that opposers to the Trump administration’s EO ‘will win’.

“If you're born here, you are a citizen, it couldn't be more clear,” Padilla said, adding that it is ‘wrong’ for Trump to pick who gets to be an American and who doesn’t.

Inside the court, ACLU lawyer Cecillia Wang has argued that the Supreme Court has already ruled in previous cases that the Ammendment means ‘virtually everyone born on US soil is subject to its jurisdiction and is a citizen’.

She concluded: “The citizenship of millions of Americans past, present and future could be called into question.”

This is a rolling news story, with fresh information regarding the oral arguments coming to light in the coming hours.