The
British Post Office scandal, also called the
Horizon IT scandal, involved the Post Office pursuing thousands of innocent subpostmasters for apparent financial shortfalls caused by faults in Horizon, an accounting software system developed by Fujitsu. Between 1999 and 2015, more than 900 subpostmasters were convicted of theft, fraud and false accounting based on faulty Horizon data, with about 700 of these prosecutions carried out by the Post Office. Other subpostmasters were prosecuted but not convicted, forced to cover shortfalls caused by Horizon with their own money, or had their contracts terminated. The court cases, criminal convictions, imprisonments, loss of livelihoods and homes, debts, and bankruptcies led to stress, illness, family breakdowns and at least four suicides. In 2024, Prime Minister Rishi Sunak described the scandal as one of the greatest miscarriages of justice in British history.