Brexit court case: Who is Gina Miller?
Gina Miller has become the figurehead of the legal fight to get Parliament to vote on whether the UK can start the process of leaving the EU - but who is she?
Ms Miller, 51, is an investment manager and philanthropist who was born in Guyana but was educated in Britain.
In an interview with Vogue in January, Ms Miller spoke of her early years in the UK after she and her brother moved to Eastbourne in East Sussex leaving their parents in Guyana.
She was sent first to Roedean School on the outskirts of Brighton at the age of 10, then to Moira House Girls' School, in Eastbourne, East Sussex.
She recalls working in local hotels as "a chambermaid or clearing up in the restaurant" while her brother did paper rounds and washed up in kitchens because their parents were not allowed to send money to the UK.
"Whilst we missed our parents dreadfully, and it was difficult juggling our home lives with homework and school, it made us who we are today," she said.
According to her LinkedIn page, she then went to university in London to study law.
Ms Miller married her first husband at 20 and they had a daughter, who has serious learning difficulties.
Her daughter, now 28, has a reading age of six, a writing age of four and very little short-term memory, Ms Miller told the Mail on Sunday.
But she describes her as having "amazing emotional intelligence" and being an inspiration to her.
In the early 1990s, she set up her own marketing company, got divorced and married the financier Jon Maguire.
Her marriage to Mr Maguire, who stood for the anti-EU right-wing English Democrat Party in the 2010 election, did not last and they divorced in 2002.
She married her third husband, hedge fund manager Alan Miller, in 2005 and they had two children.
'Black widow spider'
Ms Miller is best known for having campaigned for transparency in investment and pension funds.
In 2009, she co-founded the investment firm SCM Private and launched True and Fair Foundation - formerly known as Miller Philanthropy - with her husband.
The foundation says it supports smaller charities by providing funding and support. Charity Commission records show it spent £135,982 in 2015.
Ms Miller also began the True and Fair Campaign in 2012, which campaigns against mis-selling and hidden fund charges in the City of London's fund management industry.
According to an interview with the Financial Times in April, this has led some in the industry to label her the "black widow spider".
Speaking about a time she asked three men at an industry party why they were staring at her, she told the paper: "One of them replied that I was a disgrace and that my lobbying efforts would bring down the entire City."
Ms Miller launched the Brexit legal case with London-based Spanish hairdresser Deir Tozetti Dos Santos and the People's Challenge group, set up by Grahame Pigney - a UK citizen who lives in France - and backed by a crowd-funding campaign.
They argued the government could not invoke Article 50 of the Lisbon Treaty - starting the formal process of the UK leaving the EU - without seeking approval from Parliament.
Three London law firms - Mishcon de Reya, Edwin Coe and Bindmans - agreed to take up the case.
Ms Miller argued that only Parliament could make a decision leading to the loss of her "rights" under EU law.
But she has stressed throughout that the challenge was not an attempt to overturn the referendum decision, telling BBC Radio 4's Today programme: "We are all leavers now."
'Verging on dictatorship'
On 3 November, three judges ruled Parliament must vote on when the process can begin. The case went to the Supreme Court in December but the 11 judges rejected the government's appeal by a majority of eight to three.
Speaking after the High Court verdict, Ms Miller told the BBC the case was about scrutinising the details of Brexit, such as "how we leave, how they're going to negotiate, the directions of travel the government will take".
Ms Miller added that the challenge was about more than Brexit.
"It is about any government, any prime minister, in the future being able to take away people's rights without consulting Parliament," she said.
"We cannot have a democracy like that. That isn't a democracy, that is verging on dictatorship."
She has described herself as neither a leave nor a remain campaigner.
Asked whether she was "a remainer to your boots", she told BBC's Andrew Marr Show she had campaigned for "remain, reform and review" during the referendum.
But she said the case was now not about the referendum result, but "how we leave the EU".
She told the then-UKIP leader Nigel Farage that he should be her "biggest fan" following the controversial court case.
"This is about creating legal certainty and actually, everyone in the country should be my biggest fan because I've used my own money and a few of us we have used our own money to create legal certainty for Mrs May to move ahead," she told the programme.
Some newspapers have focused on Ms Miller's private life. However, she said "everyone has a past" and it was "totally irrelevant" to the importance of the case.
She has also spoken about the abuse she suffered as a result of her legal battle.
"I was aware there would be nastiness because anything to do with the word Brexit, people lose their minds and it's all about heart. Actually it is about your head and your heart."
She told BBC Radio 5 live she plans to report online trolls to police after receiving rape and beheading threats.
In December, a 55-year-old man from Swindon was arrested over alleged threats against Ms Miller. He was later released and, after consultation with the Crown Prosecution Service, no further action was taken, the Metropolitan Police said.
Ms Miller told the BBC's Clive Coleman that a discussion with the police concluded that employing security would be "sensible" during the Supreme Court hearing.
She also told the Andrew Marr Show she was appalled by fierce criticism by the newspapers of the High Court judges who ruled on the case.
The Daily Mail branded the judges "Enemies of the people", while the Daily Express said the ruling had marked "the day democracy died".
Ms Miller said "that is unforgivable", saying she is "a nobody and they are "the biggest brains in this country".
"They are what make us great."