Liberal Democrat leader Sir Ed Davey has apologised to the victims of the Horizon scandal for "not seeing through the Post Office's lies" during his time as postal affairs minister between 2010 and 2012.
Writing for the Guardian, Sir Ed also apologised for a delay in meeting Alan Bates, the former subpostmaster who led the charge for justice against the Post Office, claiming he had received "categorical assurances" nothing was wrong.
Davey has been repeatedly targeted by Tory MPs since the Post Office scandal returned to the headlines, sparked by an ITV drama. He was heckled in the House of Commons at one stage.
Sir Ed wrote: "The Post Office Horizon scandal is the greatest miscarriage of justice of our time and I am deeply sorry for the families who have had their lives ruined by it.
"As one of the ministers over the 20 years of this scandal, including my time as minister responsible for postal affairs, I'm sorry I did not see through the Post Office's lies - and that it took me five months to meet Alan Bates, the man who has done so much to uncover it.
"The Post Office is owned by the Government but not run by it, so the official advice I was given when I first became a minister in May 2010 was not to meet Mr Bates.
"He wrote again urging me to reconsider, and I did then meet him that October, but he shouldn't have had to wait.
"When Mr Bates told me his concerns about Horizon, I took them extremely seriously and put them to the Post Office. What I got back were categorical assurances - the same lies we now know they were telling the subpostmasters, journalists, parliament and the courts."
He added: "We can now see how the Post Office tricked and bullied men and women into giving false confessions. So many served prison time, lost their businesses and their homes, for something they didn't do. They've spent years waiting for justice, and some have died waiting.
"It is a black stain on our nation, on our government and most of all on the Post Office."
