Lisa Brennan

Year conviction was overturned:

Lisa Brennan was one of the “Post Office 39,” a group of former sub-postmasters and post-mistresses who were convicted of offences including theft, false accounting, and fraud, based on information from a computer system called Horizon which suggested that money had gone missing from post-office branch accounts.

Ms Brennan (who had become a Post Office counter clerk when she was 16 years old) was investigated based on a Horizon indicated shortfall. The prosecution case was that when she paid out cash for allowance and benefit vouchers, she removed more cash than was permitted by the voucher and kept the difference herself. She admitted that she might have made mistakes due to personal problems and work pressure, but denied theft.

She was convicted by a jury of 27 counts of theft representing a shortfall of £3,482.40. She was acquitted on five further counts. She was sentenced to six months’ imprisonment suspended for two years. She appealed against conviction on the basis of inconsistent verdicts, but this appeal was dismissed. As a result of the proceedings against her, she was forced to file for bankruptcy.

On appeal, the Court of Appeal accepted findings that bugs, errors, and defects in Horizon could, and did, cause discrepancies and shortfalls in branch accounts. The court concluded that if the Horizon data was not reliable then there was no basis for the prosecution, and the convictions were quashed. The court noted that failures of investigation and disclosure in the cases prevented the appellants from challenging, or challenging effectively, the reliability of the Horizon data.

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  • Offence: Theft / fraud
  • Jurisdiction: England & Wales
  • County: Merseyside 
  • Gender: F
  • Offence convicted of: Theft
  • Year of initial conviction: 2003
  • Year conviction was overturned: 2021
  • CCRC Referral: Y
  • Post Office Case: Y
  • Tried with others: N
  • Link to full case:
  • Crown argued case at CofA: Argued one ground but not the other
  • Retrial: N
  • Previous appeals: Unsuccessful appeal against conviction in 2004: R v Brennan [2004] EWCA Crim 1329