Protestors outside the Post Office Horizon IT Inquiry at the International Dispute Resolution Centre, London, UK, 8 December 2022. Alamy.com/Kirsty O'Connor

Private prosecutions have long been a part of judicial systems in the UK and elsewhere, providing a safeguard against inaction by the public prosecutor. Global Insight assesses the controversies surrounding their use – highlighted by the Post Office scandal – and the steps being taken to reform the system.

The Post Office scandal is described as one of the worst miscarriages of justice in British legal history. The first report published in the Post Office Horizon IT Inquiry found that 13 people may have committed suicide and at least 59 people considered ending their lives over the scandal. While the private prosecution system isn’t wholly to blame for the disaster, the findings raise the question of whether better regulation and oversight of private prosecutions could have helped prevent it.

Evidence submitted to the Post Office Horizon IT Inquiry highlighted serious failings in the Post Office’s use of private prosecutions, leading to the wrongful conviction of over 700 sub-postmasters and widespread injustice. In response, the UK government is seeking to reform private prosecutions and introduce more accountability, transparency and fairness into the system.

Private prosecutions allow individuals or organisations to bring criminal proceedings independent of the police and public prosecuting authorities. Experts have raised concerns over the proliferation of private prosecutions in the past ten years while significant funding cuts to the police and Crown Prosecution Service (CPS) have limited their ability to investigate and prosecute crimes. There is no public central database on the number of prosecutions brought by private prosecutors, and there is no duty on private prosecutors to publish data on the prosecutions that they bring.

The government said it wants to introduce stricter regulation for private prosecutions brought by organisations and agencies to ensure they meet the same standards and expectations of public prosecutors. The Ministry of Justice has consulted on proposals to introduce a binding code of conduct and system of accreditation, a public register of all private prosecutors in England and Wales and clear consequences and sanctions for those who fail to uphold the required standards.

Gareth Minty is a partner at Mishcon de Reya and Chair of the Private Prosecutors’ Association. The association is made up of roughly 150 professionals with expertise in private prosecutions and has published its own code of conduct to provide a benchmark for best practice in private prosecutions. Minty welcomes the consultation and says that a mandatory code of conduct is necessary to ensure private prosecutions are fair and in the public interest. ‘Another thing we are hugely supportive of is much better data in relation to private prosecutions,’ he says. ‘By way of example, there’s a lot of uncertainty about how many cases get referred to the CPS [which has the power to take over or discontinue private prosecutions] and the outcome of those referrals.’

Peter Hungerford-Welch, a law professor at City, University of London, says that a binding code of conduct would be a good idea to drive up standards but would require adequate enforcement to be effective. ‘The measure I would suggest to assist in the enforcement of the code would be to require the applicant for a summons to sign a declaration confirming that they have complied with the code,’ he says. ‘If it transpires that they haven’t, that is a ground to set the summons aside or to stay the proceedings as an abuse of process.’

Apart from the Post Office scandal, notable examples of private prosecutor failures include the thousands of convictions for railway fare evasion that were quashed following a ruling in 2024 that the prosecutions were brought unlawfully. These cases have caused widespread public concern over the potential for abuse in private prosecutions and the inequality of arms between wealthy corporate prosecutors and individual defendants.

Miranda Ching, a partner at Kobre & Kim and an officer of the IBA Criminal Law Committee, believes that it makes sense for organisations such as the Post Office to be more strictly regulated because of the potential impact they have on members of the public who are often vulnerable. ‘Especially in cases where the private prosecutor is responsible for prosecuting large numbers of low-income defendants, there must be additional safeguards to ensure that defence rights are protected, especially in circumstances where defendants cannot afford their own legal representation,’ she says.

Ching, a former case controller at the UK Serious Fraud Office (SFO) who acts for clients bringing private prosecutions, says that private prosecutions should be kept because there are ‘gaps within the justice system that can be remedied by lawyers and organisations other than the CPS’. In certain cases, private prosecutions have proved to be valuable tools to convict those who have committed crimes including complex frauds and intellectual property theft when public authorities lack the resources or technical expertise to do so. The parents of Stephen Lawrence – a Black teenager killed in a racist attack by a gang of white men in 1993 – decided to privately prosecute the suspects after police told them there was insufficient evidence to prosecute. The case failed to secure convictions but kept public attention on their fight for justice.

Another issue the government has consulted on related to private prosecutions is the single justice procedure. The procedure allows certain minor criminal offences to be handled by a single magistrate with a statement of mitigation from the defendant, if provided, and without a court hearing. Roughly 35 per cent of defendants dealt with via the single justice procedure are prosecuted by private prosecutors. The government wants to better protect due process in these cases by allowing prosecutors access to the mitigating circumstances provided by defendants and redesigning the notice of prosecution to make it clearer and easier for defendants to understand their rights.

Anoushka Warlow, a partner in BCL’s financial crime practice who acts for defendants in private prosecutions, says that private prosecutions will always carry an inherent risk of conflict of interest because the prosecutor is likely to be the alleged victim of the crime. ‘A private prosecutor will often have a personal interest in the outcome of the case, and that personal interest may well affect their ability to discharge their obligation to act, among other things, with objectivity and impartiality,’ she says.

Minty says that the Private Prosecutors’ Association questioned the government’s decision to exclude private prosecutions brought by individuals from the consultation. ‘PPA members, including those who have defended a number of private prosecutions, made the point that some of the most egregious cases recently have been brought by individuals.’

The cost of private prosecutions

Private prosecutions cost a large amount of money upfront because the person or organisation bringing one must pay all associated costs including investigation, evidence gathering, legal representation and court fees. If the case was brought legitimately, private prosecutors can, however, reclaim costs from central funds, whereas defendants, even if acquitted, are only able to recover legal aid rates for what they spent on the case. ‘There remains a question of whether private prosecutions are the most suitable forum, or whether the focus should instead be placed on properly resourcing public authorities in order that they can investigate and prosecute all appropriate cases of criminal wrongdoing,’ says Warlow.

In 2020, the Justice Select Committee published a report on private prosecutions which made several recommendations to address concerns about the reported rise of private prosecutions and the effectiveness of safeguards against misuse. The committee highlighted that a rise in the number of private prosecutions by wealthy organisations risks the ‘prospect of a two-tier justice system’ and recommended that the government should ‘urgently review funding arrangements for private prosecutions in order to address to inequality of the access to the right; to ensure a fair balance between the prosecutor and the defendant; and to ensure the most cost-effective use of public funds’.

The CPS told the committee in written evidence that equality of access issues arise – notably in relation to economic crime. The CPS said that the enforcement gap in the investigation of fraud by the police has led organisations and wealthy individuals to rely on prosecutions to seek justice ‘yet those most affected by fraud are unlikely to be able to fund a private prosecution’. Fraud is the most prevalent crime against individuals in England and Wales, accounting for 41 percent of all crime, according to the 2024 Crime Survey for England and Wales. The CPS recommended that the police are ‘properly resourced’ to address inequality of access issues.

‘The ability for private prosecutors to recover their investigation and prosecution costs, taken together with the absence of the requirement to put up security for costs or the risk of being liable for the defendant’s costs if the prosecution fails (unless the prosecutor is found to have behaved improperly), makes them a commercially attractive option for claims which might otherwise have been advanced in the civil courts,’ she says.

Individuals have also used private prosecutions to intimidate defendants into settling parallel civil proceedings. In the 2023 appeal case Morjaria v Westminster Magistrates Court & Others a High Court judge stayed the private prosecution ruling that the proceedings were an abuse of process because the claimant was using ‘the threat of a jail sentence’ to pressure the defendant to settle a related civil case.

In May, the UK government tabled the Victims and Courts Bill, which includes proposals to cap the amount of money that private prosecutors can claim back from the state. The changes aim to discourage the improper use of private prosecutions, reduce the risk of them being a disproportionate cost to the taxpayer and even out the inequality of arms between the prosecutor and defendants.

Minty, a former CPS prosecutor, believes that placing limits on recoverable costs for private prosecutions would drive away those who need them the most, such as charities and the public. ‘It will squeeze those at the bottom and restrict access to justice; and for those for whom costs are not an issue, it likely will have little, if any, effect in terms of their use of the criminal justice system,’ he says.

Rogers believes a better solution to address potential misuse would be to bolster the powers of magistrates to empower them to stop issuing summons for minor cases when they determine them to be a risk of disproportionate legal expenditure. ‘There are some people out there who do bring valuable prosecutions, including some prosecutions against fraudsters which have resulted in confiscation orders of millions of pounds, so there is a clear downside to disincentivising all prosecutions by aggrieved individuals,’ he says.

Statistics included in the Justice Select Committee report show that many private prosecutions cost the taxpayer more than CPS prosecutions. ‘It’s difficult to see how the taxpayer can be asked to accept that the state can afford to meet the higher cost of private prosecutions but simultaneously does not have enough resource to properly fund the police or CPS to bring the same case,’ says Warlow.

Protecting defence rights

Minty says that public awareness about private prosecutions and the rights of defendants has increased in the past ten years, following the Post Office scandal, and magistrates have started to subject applications to even greater scrutiny before granting summons for cases. ‘For example, one of the things most defendants in private prosecutions didn’t know is that you could refer the case to the CPS. Now that is universal knowledge,’ he says.

The CPS has the power to send back, take over, continue or discontinue private prosecutions referred to the prosecuting authority. The annual number of private prosecutions referred to the CPS is unclear because the prosecuting authority does not maintain a central record of the referrals. The CPS told Global Insight in response to a Freedom of Information request that between April 2020 and March 2025 the number of private prosecutions sent by the CPS to its Special Crime Division to quality assure its decisions on cases was on average 32 per year. The data shows most cases quality assured by the Special Crime Division were taken over by the CPS and brought by individual prosecutors.

The CPS says in its legal guidance on private prosecutions that CPS prosecutors should inform the Special Crime Division of any private prosecution that has been referred to the CPS, before a decision is communicated to any of the parties, to quality assure its decisions on cases.

Hungerford-Welch, who, alongside Minty and Rogers, gave evidence to the Justice Select Committee related to private prosecutions, says that an amendment to the Criminal Practice Directions – a code of practice that is not legislation but binding to the courts and parties in criminal cases – should be made which requires defendants in private prosecutions to be informed about their right to ask the CPS to review their case. He also believes it should be mandatory for defendants to be notified of the prosecutor’s application for a summons, unless there is good reason not to, to allow the accused the opportunity to make representations at a court hearing.

‘Whilst it is right that focus should be placed on achieving justice for victims of criminality, the defendant’s position must not be overlooked,’ says Warlow. ‘An improperly brought prosecution, whether private or by the state, can have serious and far-ranging consequences financially, physically, emotionally and reputationally.’

Alice Johnson is the IBA Multimedia Journalist and can be contacted at alice.johnson@int-bar.org.