Nick Wallis has been investigating the Post Office Horizon scandal for more than a decade, revealing the true story of the Post Office's persecution of its own Sub Postmasters.

A long campaign for justice has forced the launching of a wide ranging public inquiry, which started hearing evidence last year. The Post Office and the government have also agreed to run three separate compensation schemes to try and make things right.

The inquiry is forcing extraordinary evidence to light. It implicates senior staff in stunning cultural failings. But even as this picture emerges, campaigners and politicians following the scandal are ringing alarm bells about how the Post Office is behaving now.

Key people who are accused of covering up the scandal are still in their jobs, even as the Post Office claims to have turned over a new leaf. Post Office bosses recently generated fresh outrage by awarding themselves generous bonuses for helping the inquiry complete its work, despite the fact that the inquiry has only just started. Post Office CEO Nick Read has apologised and returned the bonus, after the inquiry rebuked the Post Office directly.

And, as Nick Wallis explores the Sub Postmasters' fight for fair compensation, he discovers that many feel the Post Office is treating them now just as they have treated them throughout the worst of the scandal.

In a new edition of The Great Post Office Trial, hearing from people at the heart of a fresh wave of revelations, Nick discovers a shocking truth - the scandal, even as it is being investigated by a public inquiry, is far from over.

Presenter: Nick Wallis

A Whistledown production for BBC Radio 4