Jo Hamilton (subpostmaster)

Josephine Hamilton OBE (born 1957[2][3]) is a former subpostmaster and a campaigner for justice for victims of the British Post Office scandal.

She was convicted of false accounting, received a supervision order and had to pay the Post Office £36,000 although it was money she did not owe.

She went on to be a founding member of the Justice for Subpostmasters Alliance (JFSA) and one of the 555 litigants in the successful group legal action of Bates & Others v Post Office Ltd.

At first the system worked well, and it was only after the Post Office installed a chip-and-pin machine in 2003 that she began to experience discrepancies in her accounts.

[6] In November 2007, Hamilton took legal advice and pleaded guilty to a lesser offence of false accounting in the hope of avoiding a prison sentence.

[7] Although Hamilton had been told that she was the only person experiencing problems with Horizon, she was in fact one of hundreds of people prosecuted by the Post Office in similar circumstances.

[4]: 91–2  Later that year she was one of the founding members of the Justice For Subpostmasters Association (JFSA) and attended the inaugural meeting in Fenny Compton village hall.

[4]: 101–3  In December 2009, Hamilton met with her MP, James Arbuthnot, who believed what she was saying and became the leader of a group of MPs whose constituents had had similar problems with Horizon.

[4]: 101–3 Hamilton was one of the 555 subpostmasters who joined the group legal action of Bates & Others v Post Office Ltd, heard by Justice Fraser in the High Court at the Rolls Building in London between 2017 and 2019.

[11] There were two grounds of appeal: firstly that the trials had been unfair because Horizon data was unreliable; secondly that the prosecutions had been an "affront to the public conscience".

[11]: 114 Hamilton had known since October 2020 that the Post Office was not going to contest her appeal but was at court on 23 April 2021 to hear the judgment delivered and her conviction formally overturned.

[13] An independent review into the Horizon scandal was set up in September 2020, chaired by retired High Court judge Sir Wyn Williams.

[16] Hamilton was appointed Officer of the Order of the British Empire (OBE) in the 2025 New Year Honours for services to justice.