Thursday 13 October 2016 9:00 am

The woman behind the Brexit row: Gina Miller tells City A.M. why she took the government to task over Article 50

Gina Miller's high-profile court case over the triggering of Article 50 – the process by which the UK would start to leave the EU – begins today (Thursday 13 October).

Miller's action is one of many brought after the public voted in June for Britain to leave the European Union, but hers has become the bellwether case.

Constitutional law, once a matter that only excited academics, has taken centre stage since the public voted for Brexit.

A row quickly raged over whether triggering of Article 50 is something which government can do by prerogative or a matter which would require a new law to be passed by parliament.

But, now, the situation is no longer hypothetical. In July, the high court decided a case on the issue would be heard in October, and, although the issue has been brought to court by numerous interested parties, the case of Gina Miller has been picked to lead the plight. 

"I think it's only fair that we have a grown-up, serious conversation about the trigger of Article 50 and the constitutional steps that need to be taken to do that," Miller told City A.M.

Read more: Bank of England: "No clear evidence" of slowdown since Brexit vote (yet)

She continued: "The majority of MPs work very hard to represent their constituents and they're [in parliament] because they believe in taking civic responsibility and those are the people, the hundreds of them in parliament, that we need to debate this properly."

Miller, who works in investment management, stressed her case was not an attempt to subvert the will of the majority who voted to leave the EU. 

However, the businesswoman has concerns that the public were misled in the run up to the referendum and that businesses did not get a proper chance to have their voice heard.

"It was very difficult pre-the vote to talk in an expert way because suddenly all experts became the doom mongers and we were lying," she said. 

Read more: City representatives at civil war over Brexit response

Not everyone approves of what Miller and the other anonymous clients represented by her solicitor, Mishcon de Reya, are doing. When the firm first revealed it was readying itself for legal action, various Eurosceptic MPs slammed the idea of bringing Brexit into the courtroom.

The London law firm has since received such a level of abuse that Sir Brian Leveson, who oversaw an initial hearing to create a timetable for the case, called it "aggressive, abusive and threatening" and warned it could be considered contempt of court. 

However, Miller scoffs at her critics by pointing out her legal argument is founded on one of the very things many Brexiteers argued for ahead of the vote.

Read more: An independent Scotland inside the EU would be an economic powerhouse

"The Leavers were arguing about sovereignty…well, this is an issue of sovereignty of parliament," she said. "You need to have a considered debate about what government needs to do before it makes that irreversible step."

Miller added: "This is not about politics. This is about process and the rule of law."

Miller may want this to be a matter for parliament but it doesn't mean the financial services pro is without her own opinion on what Brexit should look like.

"In an ideal world, what I'd like us to end up with is some sort of associative membership or somewhere that we can actually lead reform in the EU," she said. "I think that's what we should be pushing for."