UPDATED 2.39PM: A hearing into whether John Banks should face a retrial on a charge of filing a false electoral charge is underway in the Court of Appeal.

The hearing was ordered after Banks' lawyer was given fresh material about the controversial lunch at the Dotcom mansion on June 5, 2010.

His lawyer David Jones QC argued a memorandum containing information at odds with that supplied at the trial, about a lunch between Mr Banks and Kim Dotcom in June 2010.

Mr Jones says the information should've been disclosed - as it would've had a serious impact on any decisions by the Court of Appeal.

Outside court Banks told media the judicial process has been harrowing, and torture for himself and his family.

"None of us are above the law and when confronted with these allegations, we have to stand up and be counted.".

"One thing I won't accept, I won't accept any liability for something I've never done."

The court's decision has been reserved.