Mr Bates vs The Post Office director delighted by audience reaction

James Strong said it was important to tell stories like the Post Office Horizon scandal

The reaction to an ITV drama about the Post Office scandal has been "beyond our wildest dreams", its director says.

Mr. Bates vs The Post Office tells the story of hundreds of postmasters who were wrongly accused of theft, fraud and false accounting.

It happened because the IT system they were using, Horizon, was defective.

James Strong, who directed the series, says the audience figures have been "astonishing" .

Former Post Office CEO Paula Vennells has handed back her CBE following the reaction to the programme.

Between 1999 and 2015, the Post Office prosecuted 736 sub-postmasters and mistresses based on the faulty IT system.

More than 700 branch managers were given criminal convictions - only 93 of which have been overturned

Justice Secretary and Cheltenham MP Alex Chalk said in the House of Commons on Tuesday that a law to quash hundreds of convictions was being "actively considered".

Two former post office managers in Gloucestershire who were among the 736 accused of wrongdoing said they are still fighting for further justice.

Prime Minister Rishi Sunak is expected to address the scandal in the House of Commons during Prime Minister's Questions at 12:00 GMT.

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Speaking on BBC Radio Bristol Mr Strong said the impact of the series is "astonishing".

Mr Strong, who is from Bristol, said: "It is beyond all of our wildest dreams that this has had such an impact.

"To see it grasp the whole nation and see it front page in the newspapers every single day since.

"To see the figures where we have seen - nine, 10 million come in and watch the first episode - it really is astonishing."

Some of the actors accepted lower fees to be in the drama, said Mr Strong

He added: "We did not have any sales anywhere abroad, the money [for the series] was really tight. The actors, everybody, took a pay cut to do it.

"It is really important that this drama shows these kinds of stories, it is really important that we dramatise them.

"The power is there, so we have to do more."

Darren Jones, Bristol North West MP and former chair of the business committee, told BBC Radio Bristol that the coronavirus pandemic stopped a committee hearing with the Post Office and Fujitsu taking place.

By the time restrictions were lifted, a statutory inquiry was about to start and the two could not happen simultaneously.

Mr Jones added that a "whole host of lessons that need to be learned".

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• Fujitsu to be held accountable, says government

• How a Japanese firm became part of the Post Office scandal

• 'Post Office charges led to my breakdown'

• Ex-Post Office boss was shortlisted to be bishop

• The village where Post Office scandal battle began

• Ex-Post Office boss to hand back CBE

He said: "One of the key ones is why is it that from the IT engineers through to employees at the Post Office, to senior directors, to the board, to the non-executive directors, to the government officials, to the court process, was it not clear that these victims were innocent?

"Why could they not defend themselves? One of the key reasons is that the law on computers is out of date.

"It assumes that computers are right unless the defendant or in this case the victim can prove otherwise.

"Because of the lack of those checks and balances, and the lack of access to information, those sub postmasters were never going to be able to defend themselves within the law.

"That should be reviewed but equally the governance and accountability around organisations, whether they are privately or publicly owned, needs to be considered so that these types of miscarriages of justice can never happen again."

Meanwhile, Gloucester MP Richard Graham said he is going to investigate whether the closure of a post office in Kingsholm is related to the scandal.

He told BBC Radio Gloucestershire: "I do not know for sure but I am going to be asking the questions whether that decision was based on some false accounting and a belief that the post office was losing money when in fact it almost certainly was not.

"There were 500 pensioners who were getting their money from Kingsholm post office who were severely disadvantaged by that decision.

"I think there will be more cases like that of post offices closing. I am afraid this story is going to go on for a long time."