Private prosecutor’s failure to fully investigate and disclose infor-mation leads to 39 historic convictions quashed (Hamilton v Post Of-fice)

Sandip Patel QCManaging Partner, Aliant Law

Corporate Crime analysis: Following 42 referrals by the Criminal Cases Review Commission (CCRC), the Court of Appeal, Criminal Division, allowed 39 appeals of historic prosecutions brought by the Post Office Ltd as private prosecutor. The court held that the prosecutor’s failure to investigate and disclose material which would have assisted the defence on matters essential to the prosecution case relating to the Horizon IT system amounted to an abuse of process. The proceedings were unfair, and the conduct was so serious as to be an affront to the public conscience. These cases are a salutary reminder to institutional private prosecutors that investigation and disclosure processes must be robustly applied without regard to self-interest, and that a full investigation of issues raised by the accused in their defence must be carried out. Written by Sandip Patel QC, managing partner, and Barry Smith, associate, at Aliant Law.This analysis was first published on Lexis®PSL on 26/04/2021’

Hamilton and others v Post Office Ltd [2021] EWCA Crim 577

What are the practical implications of this case?

This judgment establishes that prosecutions brought by the Post Office Ltd amounted to perhaps the most wide-ranging and systematic miscarriages of justice in England and Wales. It underlines the importance of private prosecutors complying with their duties of investigation and disclosure, and is a rare example of the court finding that a private prosecutor has given preference to its own interests over its duties to the court and defence.

The court has clarified that where an abuse of process is established, the same conduct which may render a trial unfair may also amount to an affront to the public conscience. Practitioners will be aware that establishing the latter may be important where claims for malicious prosecution are contemplated.

In addition, this case is an unusual example of the Court of Appeal admitting fresh evidence of the post-conviction conduct of a prosecutor where it sheds a light on the prosecutor’s approach to the original matter, as well as admitting in evidence findings from a related civil judgment.

This decision underlines the importance of institutional prosecutors having robust systems in place to ensure so that where there are common disclosure issues across a number of cases it is possible for these to be identified, and cross-disclosure made, where the disclosure test is met for material held in respect of other cases.

What was the background?

Following the judgments in Bates and others v Post Office Ltd [2019] EWHC 606 (QB), [2019] All ER (D) 100 (Mar) and Bates and others v Post Office Ltd [2019] EWHC 3408 (QB), the CCRC referred convictions of fraud, theft and false accounting of 42 sub-postmasters to the Court of Appeal. The appellants were all prosecuted by the Post Office Ltd between 2003 and 2013 as private prosecutor. The convictions were all said to have been reliant, in part, on the accuracy and reliability of the Horizon IT accounting system which was utilised by the Post Office Ltd. The findings of Fraser J in the Bates cases included that the Horizon IT system, contrary to the position adopted by the Post Office Ltd, was not remotely robust or reliable. It contained various bugs and errors which gave rise to a material risk that an apparent shortfall in the accounts of a branch post office did not in fact reflect missing cash or stock, and was caused by one of the bugs or errors. The Post Office Ltd was said to have failed to properly investigate complaints of this made by sub-postmasters, and also to disclose evidence of the bugs to the appellants. It was this conduct which amounted to an abuse of process.

The Post Office Ltd conceded that the convictions of four appellants were unsafe on both limbs of the test in R v Maxwell [2010] UKSC 48, ie that the proceedings had been unfair (‘limb 1 abuse’), and also that the conduct of the prosecutor was an affront to the public conscience (‘limb 2 abuse’). For 35 appellants, the Post Office Ltd conceded that investigatory and disclosure failings relating to the Horizon IT system amounted to a limb 1 abuse where Horizon data was essential to the conviction. The Post Office Ltd did not accept that limb 2 abuse was made out. The Post Office Ltd contested three appeals on the basis that the Horizon IT system was not an essential part of the prosecution case.

The Post Office Ltd conceded that in four cases limb 2 abuse was made out for case-specific reasons. These included that the practice of charging both theft and false accounting amounted to an undue pressure to plead guilty; that the prosecution process was being used to enforce repayment; and that guilty pleas to alternative offences were conditional on Horizon not being criticised.

What did the court decide?

The court held that the concessions made by the Post Office Ltd were properly made on limb 1. The Bates cases established that there were relevant defects in the Horizon system and that the Post Office Ltd knew that there were serious issues regarding the reliability of Horizon. It had a clear duty to investigate all reasonable lines of enquiry and to consider (and make) disclosure of material which might reasonably undermine its case. There was no adequate consideration, investigation or disclosure of Horizon problems, and no attempt was made to investigate the assertions of sub-postmasters that there must be a problem. This consistent failure to be open and honest was only explained by a strong reluctance to say or do anything which might lead to other sub-postmasters knowing about those issues, and effectively steamrolled over anyone who sought to challenge its accuracy. There was no basis for the prosecution if the Horizon data was not reliable, and the prosecutor’s failure to investigate and disclose prevented the appellants from challenging the reliability of the data. A fair trial was not possible.

The court confirmed that the fact that some appellants had pleaded guilty was not a bar to the conviction being found to be unsafe where the plea was founded upon the irregularity of non-disclosure, applying to R v Togher and others [2000] Lexis Citation 4390, [2000] All ER (D) 1752.

In respect of limb 2, the court held that it was not necessary in law for an appellant who raises limb 2 abuse to prove misconduct beyond that which establishes limb 1 abuse. As a matter of principle, there was no reason why the same misconduct cannot provide the basis for a finding of both categories of abuse, and the court accepted that depending on the nature and degree of the abusive conduct, the same acts or omissions may both render a fair trial impossible (limb 1) and make it an affront to the conscience of the court to prosecute at all (limb 2).

It was held that the investigatory and disclosure failures were so egregious as to make the prosecution of the Horizon-related cases an affront to the conscience of the court for the following reasons:

  • the Post Office deliberately chose not to comply with its obligations in circumstances where the prosecution depended on the reliability of Horizon data
  • it did so against a background of asserting that sub-postmasters were contractually liable to make good all losses, and assumed dishonesty on the part of individuals of otherwise good character
  • the prosecution’s approach therefore effectively sought to reverse the burden of proof
  • the Post Office’s approach to investigation and disclosure was influenced by what was in the interests of itself, rather than the legal obligations on a prosecutor
  • there was evidence of systemic failures of many years, and that the later events shed legitimate light on the approach to earlier prosecutions
  • the Post Office knew of problems with Horizon from 2000 onwards, and was able to obtain all the relevant information from its contractor Fujitsu if it wanted to, and that the expense of doing so did not justify its failure to comply with its legal duties
  • the failings in this case went beyond simple non-disclosure. The consequences of the prosecutions were severe for the sub-postmasters, all suffering financial losses, in some cases bankruptcy, breakdowns in family relationships, breakdowns in health, and the shame and humiliation of being reduced from a respected local figure to a convicted criminal
  • the prosecutorial failings directly implicated the courts. If the full picture had been disclosed as it should have been, the public interest in prosecution would have been heavily outweighed by the need to maintain public confidence in the criminal justice system. There was no reason for the prosecutions to be hurried through, and no excuse for the Post Office’s failures
  • the court was particularly troubled by contemporaneous internal documents in which the Post Office Ltd expressed concern that the disclosure of one case of problems with Horizon could have an impact on other cases. Public confidence in the criminal justice system would be severely damaged if a prosecuting authority were permitted to give priority to this over compliance with prosecutorial duties

The fully contested appeals were dismissed, the court finding that, on their specific facts, the reliability of Horizon evidence was not an essential part to those convictions.

Case details

  • Court: Court of Appeal, Criminal Division
  • Judges: Lord Justice Holroyde, Mr Justice Picken and Mrs Justice Farbey
  • Date of judgment: 23 April 2021

Sandip Patel QC is managing partner, and Barry Smith an associate, at Aliant Law, and both are members of LexisPSL’s Case Analysis Expert Panels. If you have any questions about membership of these panels, please contact [email protected].


Contributing Advisors

Muthupandi GanesanBarrister, Partner, Aliant Law

Barry SmithSolicitor/Associate, Aliant Law