Mr Banks, who was behind prominent Brexit campaign group Leave.Eu, was being investigated by the Electoral Commission but they passed the probe along, saying there were reasonable grounds to suspect he was not the “true source” millions of pounds worth of loans to the unofficial campaign group.
Prime Minister Theresa May is also under pressure to clarify whether there is any truth behind claims she blocked an investigation into Mr Banks before the Brexit referendum in 2016.
Mr Banks has previously denied any wrongdoing and is now scheduled to appear on the Marr on Sunday programme.
But campaigners are questioning the judgement of giving Mr Banks a platform. MEP Molly Scott Cato and actor-activist Robert Llewellyn both think the BBC is missing the mark.
Molly Scott Cato wrote: “How can the BBC think this is in any way appropriate? Why would you give someone under police investigation and a suspected traitor the oxygen of publicity and such a massive advantage before possible trial. Does this even prejudice the chance of a fair trial?”
Robert Llewellyn tweeted: “I’m so glad you’re giving this poor man even more airtime. I mean, you’ve only had Faragé on 67 times in the last 3 years. I’m sure it’s perfectly normal practice to allow someone being investigated for criminal offences to prejudice a potential trial.”
A BBC spokesperson told The I: “There is strong public interest in an interview with Arron Banks about allegations of funding irregularities in relation to Leave.Eu and the 2016 EU Referendum. “The Electoral Commission has laid out concerns about this in public and it is legitimate and editorially justified for Andrew Marr to question Mr Banks robustly about them, which he will do on Sunday morning.”
This article appeared on our sister paper site, The i