What actually happened in the Post Office Horizon scandal?

It's been dubbed the biggest miscarriage of justice in UK history, but what actually happened in the Post Office scandal?

ITV's Mr Bates vs The Post Office landed on ITVX at the beginning of the new year, and appears to have reignited calls to fight the injustice that began to take place way back in 1999.

The Post Office scandal wrongly accused more than 700 post office workers of stealing - all because of faulty IT software. 

Errors in the faulty accounting software made by Fujitsu sparked the scandal. The 'Horizon' system made it look like money was disappearing from Post Office branches, with the blame then falling at the feet of those running them.

Between 1999 and 2015, hundreds of workers were wrongly accused of theft, fraud and faulty accounting.

Many involved went to prison, others had to make large payouts as a result and in some tragic cases, former workers took their own lives.

Tracy Felstead, who was 19 years old at the time, explained she'd been sent to what was one of Western Europe's largest female prisons.

"There was no way I was pleading guilty to something that I hadn't done," she said.

Speaking to ITV's This Morning, Miss Felstead also addressed the challenges of taking on the establishment.

"You couldn't defend yourself."

One of the names mentioned around this story is Paula Vennells. She ran the Post Office while hundreds of false accusations were made.

Ms Vennells refused to co-operate in the ITV drama.

She's also refused all interview requests since the scandal emerged, but will face scrutiny later this year at the Post Office Horizon IT inquiry.

Her lawyers explained she was "unwavering in her support for the inquiry" but it would be "inappropriate to comment" or "participate in an interview."

Over the last several years, Ms Vennells has issued a series of statements saying she is "truly sorry" for the suffering caused to "innocent postmasters," her lawyers added.

A petition for her to lose her CBE honour has been signed by more than a million people online and the number continues to grow. Rishi Sunak has also pledged his support for the move.

Another under pressure is Lib Dem leader Sir Ed Davey. He was the minister responsible for the Post Office during the coalition government.

He says he "understands" why people are angry but accused the Post Office of lying to him on an "industrial scale".

Discussions are underway about potentially clearing those involved completely, according to the prime minister.

The victims of the Post Office scandal are left hoping that greater public awareness and political momentum will only help end their search for justice.

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