The Fund Manager Blocking Johnson’s Brexit Sprint Gina Miller wins another bid to impose scrutiny on U.K. divorce from EU Gina Miller in London on Tuesday. Soon after the 2016 Brexit referendum, Ms. Miller began to agitate against the U.K. government’s plan to leave the EU. Photo: henry nicholls/Reuters By Max Colchester Updated Sept. 25, 2019 3:59 am ET LONDON—Behind the latest bout of constitutional upheaval to envelop Brexit stands a Guyanese-born fund manager, Gina Miller. Outside the U.K. Supreme Court in London on Tuesday, Ms. Miller celebrated her latest victory against the government: a momentous ruling that Prime Minister Boris Johnson had unlawfully suspended Parliament. Ever since the 2016 Brexit referendum, Ms. Miller has led a rear-guard legal action against the government aimed at frustrating what she says is its attempt to push a rapid split with the European Union without proper parliamentary scrutiny. You may also like Up Next U.K. Court Rules Boris Johnson's Parliament Suspension Was Illegal The U.K.’s Supreme Court ruled that Prime Minister Boris Johnson acted unlawfully when he suspended Parliament for five weeks using a procedure known as prorogation. Photo: Stefan Rousseau/Zuma Press “We have had to twice in three years come to the Supreme Court to ensure the government does not put itself above the law,” Ms. Miller told a cheering crowd. “This prime minister must open the doors of Parliament tomorrow.” Ms. Miller, who co-founded the investment company SCM Direct, is one of a crew of campaigners who have repeatedly tripped up the government in an unexpected plot twist to the Brexit saga. Those legal challenges have seen the country’s top court twice rule to reinforce Parliament’s oversight of the Brexit process. The decisions have opened an avenue to future court cases on constitutional matters, which up until now were a rarity in Britain. “This is a landmark case,” Ms. Miller said on Tuesday. “No prime minister can now ever bypass Parliament when it disagrees with them.” Born in the then-British colony of British Guiana in South America, Ms. Miller, who is now 54, was sent at age 10 by her parents to be educated in the U.K. Later, when her parents struggled to pay her school fees, she worked in a hotel while she studied. She attended university in London to study law but didn’t complete her degree. In the early 1990s, she set up her own marketing company. Ms. Miller emerged from the Supreme Court building after Tuesday’s ruling. Photo: Hollie Adams/Getty Images Ms. Miller and her third husband, Alan Miller, set up an investment company in 2009. She earned a reputation campaigning against hidden fees in asset management—telling the Financial Times that her lobbying earned her the nickname “the black widow spider” in industry circles. Within days of the result of the 2016 Brexit referendum, Ms. Miller began to agitate against the government’s plan to leave the bloc. Ms. Miller and Brazilian hairdresser Deir Dos Santos launched a legal campaign to ensure the government couldn’t trigger the process of quitting the EU without Parliament’s approval. Grahame Pigney, a France-based expatriate who used crowdfunding from more than 4,000 people to pay for lawyers, joined the suit as a co-party. Three legal firms, including Mishcon De Reya, agreed to represent them. The group won. The Daily Mail newspaper branded the judges that sided with Ms. Miller as “enemies of the people.” Ms. Miller received death threats. Lawmakers voted to start the Brexit process soon after—but opposition and pro-EU lawmakers forced the government to offer a “meaningful vote” on any divorce deal the U.K. reached with the EU. Parliament has rejected the government’s deal three times and is now deadlocked. Ms. Miller’s critics say the legal challenges are blocking the government from delivering on a decision a majority of voters made to quit the EU. Ms. Miller, who voted to remain in the bloc during the 2016 referendum, says she wants more transparency in the Brexit process, and to empower lawmakers. A majority of lawmakers in Parliament voted to stay in the EU, a fact that euroskeptics have bemoaned. When asked if she thought Brexit should happen, Ms. Miller said that leaving the EU without a deal would be a bad outcome. Recently, she launched RemainUnited, a website that promoted tactical voting to prevent the euroskeptic Brexit Party from gaining sway in European Parliament elections. Ms. Miller said her lawsuits are largely funded by herself and several of the lawyers who work with her pro-bono. Ms. Miller’s latest legal challenge was triggered after Prime Minister Johnson announced a five-week suspension of Parliament beginning this month. Mr. Johnson said the suspension was a routine matter aimed at clearing the parliamentary slate so that he could present a new agenda. Ms. Miller and a group of Scottish lawmakers—who took a separate case through the Scottish courts—said the move was intended to stop Parliament passing laws and scrutinizing the government’s Brexit plan. Ms. Miller dubbed the government “The Johnson hijackers.” Mr. Johnson’s weekslong prorogation was the longest since 1945. Last month, as anti-Brexit protesters chanted “Gina, Gina” outside an English high court, judges initially threw out the complaint saying it wasn’t for the courts to rule on such a matter. A Scottish court, however, ruled the move was unlawful. Appeals to both complaints were heard at the U.K. Supreme Court in London. On Tuesday, the 11 judges ruled that the government had acted unlawfully and that the executive isn’t allowed to suspend Parliament to prevent the scrutiny of its policies. Mr. Johnson said he “strongly” disagreed with the decision. Parliament reopens on Wednesday. Ms. Miller said she would continue to watch the situation closely. “I will carry on exactly as I have for the last three years.” Corrections & Amplifications Gina Miller’s third husband is Alan Miller. An earlier version of this article misnamed her husband as Mark Miller. (Sept. 25) Write to Max Colchester at max.colchester@wsj.com https://www.wsj.com/articles/the-fund-manager-blocking-johnsons-brexit-sprint-11569350964