One Nation senator Malcolm Roberts looks set to lose his parliamentary seat for breaching Section 44 of the Australian Constitution after the High Court ruled today that he was “a citizen of the United Kingdom by descent at the time of his nomination”.

The matter has been set down for hearing by the Full Court of the High Court of Australia, sitting as the Court of Disputed Returns, together with similar cases involving three other senators, two former Greens senators and deputy prime minister Barnaby Joyce on October 10, 2017.

Section 44 of the Constitution bars people with citizenship in a country other than Australia from standing for election.

Roberts was born in India in 1955 to a Welsh father, and previously claimed that he “never held any citizenship other than Australian”.

But Justice Patrick Keane did not accept that characterisation, chastising Roberts for a “reliance on his highly subjective appreciation of the importance of commonplace incidents of his familial experience”.

Here’s part of his judgment:

It is significant that Senator Roberts did not suggest, either in his affidavit, or in his emails, or in the course of his cross-examination, that he believed that in some way, expressly or impliedly, he renounced his British citizenship when he obtained Australian citizenship by naturalisation.

The absence of any such suggestion highlights that there was no rational basis for the belief that he was always and only an Australian citizen.

The absence of any rational basis in fact for that belief meant that Senator Roberts was driven to support his position by reliance on his highly subjective appreciation of the importance of commonplace incidents of his familial experience.

But the court heard that the senator’s father, who died last year, registered his son with UK authorities. Senator Roberts said that evidence was “amongst [his] father’s papers” but he did not “remember reading it prior to the controversy that led to this case”.

As a teenage adult, Roberts subsequently signed an application to become an Australian citizen in 1974, but told the court he did not remember reading or signing the form, which detailed his citizenship at the time as “(British) UK+COLS”. He believed his sister filled out the form for him.

When he was filling out his senate candidacy forms last year, Roberts told the court that he recalled that his father never called him British, and said that given his “pleasantly sarcastic” nature, his father would have gently teased him about it if that was the case.

The court heard that Roberts attempted to clarify if he was a dual national before nominating.

He wrote an email to two addresses he found on the internet on May 1, 2016.

The email said in part:

My birth was registered with London. Around 1973 my father and I and my brother and sister became Australian citizens. Dad died recently but was getting a partial British pension from his younger years working in Wales.

My inquiry is this: Am I still a British citizen?

I am NOT seeking British citizenship. If I am still a UK citizen I need to renounce it for compliance with electoral legislation in Australia.

Please advise whether or not I am still a British citizen?

If I am a British citizen, how do I renounce it?”

He wrote again on June 6 to the same email addresses complaining about a lack of response, and also sent it to a third email address saying:

As there was no reply to my email last month (see below) and although I am confident I am not a British citizen, with this email I renounce any British citizenship should it exist.

If I remained a British citizen after gaining Australian citizenship on 17th May 1974, please accept this email notice renouncing any remnant British citizenship, effective immediately.

The deadline for senate nominations was June 9. Roberts submitted his.

But Justice Keane did not accept that Roberts had enough time to renounce his citizenship beforehand.

“I find that Senator Roberts’ email of 6 June 2016 was not apt to lead to a termination of his British citizenship because it did not contain a declaration of truth,” he wrote in the judgment.

“Senator Roberts could have sought professional advice on the issue, or he could have communicated by telephone or email with the UK High Commission in Canberra in order to establish his position. He did neither of these things.”

The court heard that “around August 2016” his wife became concerned about his citizenship position, and encouraged him to try to obtain written evidence of his status.

Roberts told the court his wife “did extensive Internet searches over the next few days and eventually tracked down the UK Home Office”.

They wrote to it on September 10, 2016 with a similar message to the emails and received a reply on September 27 from the UK Home Office, stating that from the information provided “you appear to have a claim to British nationality via descent”. It offered advice on how to renounce citizenship.

Roberts or his wife replied that day that “I will now complete administrative processes linked in your email and thereby more formally renounce any and all claims to British nationality and allegiance”.

They wrote again on October 3, had a reply two days later, and on November 1, Roberts completed the UK Home Office renunciation form, stating he “maybe” was a British citizen. His wife posted the form the following day. The Home Office confirmed receipt on November 17, and sent a letter on December 5 saying that was the date Roberts had successfully registered his renunciation.

“I find that Senator Roberts knew that he did not become an Australian citizen until May 1974. I find that, as at the date of his nomination for the Senate, he knew that there was at least a real and substantial prospect that prior to May 1974 he had been and remained thereafter a citizen of the United Kingdom,” Justice Keane wrote.

His full judgment is here.

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