Mr Ball has worked full-time on the case since June 2016, and has raised more than £200,000 through a crowdfunding campaign to pay for the “Brexit Justice” private prosecution.
He founded Brexit Justice in June 2016 and has been “working relentlessly to bring an end to lying in politics ever since”, according to the Brexit Justice website.
A short profile says he is a speaker and a writer and previously worked to reform higher education in the UK.
A post on his crowdfunder page said he would be “going quite quiet for this section of the process”.
Earlier this month, he wrote: “I take my responsibilities to secure coverage and funding very seriously but I take my responsibilities to respect the court process even more seriously.
“In short, I will be going quiet for now.”
Mr Ball has previously said: “This case is a world first, it has never happened before.
"A Member of Parliament has never been prosecuted for misconduct in public office based upon alleged lying to the public.
“My backers and I aspire to set a precedent in the UK common law making it illegal for an elected representative to lie to the public about financial matters.”