The Post Office Horizon scandal has been called the UK’s most widespread miscarriage of justice, after hundreds of people were prosecuted on the basis of data from faulty software.
The scandal led to widespread public anger, partly as a result of a hit TV drama, and has been the subject of a lengthy inquiry.
The first part of the report from the official inquiry into what happened, released in July 2025, revealed the full extent of the suffering of sub-postmasters and others affected by being wrongly accused of stealing money and false accounting.
What happened and how many people were affected?
More than 900 sub-postmasters were prosecuted because of incorrect information from the Horizon computer system.
Many sub-postmasters went to prison for false accounting and theft, and others were financially ruined.
The Post Office itself took many cases to court, prosecuting 700 people between 1999 and 2015. Another 283 cases were brought by other bodies, including the Crown Prosecution Service (CPS)
https://www.bbc.com/news/articles/c1wpp4w14pqo
In 2017, a group of 555 sub-postmasters – led by campaigner Alan Bates, who has since been knighted – took legal action in a landmark court case against the Post Office.