Why conviction rates still matter in measuring prosecutorial performance

The debate over how to measure prosecutorial success in South Africa has become increasingly prominent in academic and policy discourse.

Scholars, criminal justice commentators and researchers have questioned the National Prosecuting Authority’s (NPA’s) continued reliance on conviction rates as a principal measure of prosecutorial performance. Their critique is that conviction statistics may oversimplify the complexity of criminal justice outcomes and obscure broader systemic weaknesses within the criminal justice system.

This critique raises important considerations concerning accountability, fairness and institutional effectiveness. However, it often understates a fundamental constitutional reality: the primary mandate of a prosecuting authority is to prosecute criminal matters successfully, fairly, and in accordance with the law. In this regard, conviction rates remain a legitimate and internationally recognised indicator of prosecutorial effectiveness when properly contextualised within the broader criminal justice environment.

This debate assumed renewed significance following the appointment of the current National Director of Public Prosecutions, Advocate Andy Mothibi, in February 2026, when the NPA was revising its Annual Performance Plan to align with the Medium-Term Development Plan. Outcome three of the Medium-Term Development Plan emphasises the development of a capable, ethical and developmental state, while encouraging greater alignment among institutions within the criminal justice system in pursuit of a common objective: justice for victims of crime.

Intrinsically interdependent

Within this framework, the relationship between the NPA and the South African Police Service (SAPS) is intrinsically interdependent. Prosecutorial success is inextricably linked to the quality of police investigations, evidentiary gathering, forensic analysis and witness management. Yet it is unrealistic to expect that all crimes committed will be reported, adequately investigated, and successfully prosecuted. Resource constraints, investigative limitations and the complexity of criminal activity render such expectations impracticable in any criminal justice system.

Consequently, conviction rates must be understood within their proper institutional context. They do not measure overall crime levels, policing effectiveness, or reporting rates. Rather, conviction rates assess the proportion of prosecuted cases that culminate in guilty verdicts after judicial adjudication. In this respect, conviction rates provide insight into prosecutorial discretion, evidentiary assessment, trial preparation, and courtroom competence.

In the contemporary South African context, this distinction has become increasingly important. Criminal prosecutions are now unfolding within an environment characterised by organised criminal syndicates, sophisticated financial crimes, cybercrime, extensive corruption networks, digital evidence challenges, forensic backlogs and heightened witness intimidation.

These developments have fundamentally altered the prosecutorial landscape. Prosecutors are increasingly required not merely to present evidence in court, but to coordinate multidisciplinary litigation strategies involving digital forensic analysis, financial intelligence, asset tracing and complex evidentiary reconstruction across multiple jurisdictions.

Recent performance trends within the NPA demonstrate that conviction rates remain a meaningful indicator precisely because they reflect prosecutorial performance under these increasingly difficult conditions. The NPA’s 2024/25 annual report indicates that organised crime conviction rates have consistently remained above 90% over five years, despite increased case complexity and resource pressures.

Capacity to adapt

Cybercrime prosecutions similarly achieved conviction rates approaching or reaching 100% in certain reporting periods. These outcomes suggest not merely institutional efficiency, but a capacity to adapt prosecutorial methods to evolving forms of criminality.

Importantly, current prosecutorial trends also reveal a shift away from traditional reactive prosecution toward intelligence-driven and prosecutor-led investigative models. The NPA has increasingly prioritised dismantling organised criminal enterprises through racketeering prosecutions, money laundering investigations, and asset forfeiture proceedings rather than focusing solely on lower-level offenders. This reflects an international prosecutorial trend in which conviction rates are evaluated alongside the complexity and strategic significance of prosecutions secured.

At the same time, conviction rates also illuminate the practical consequences of systemic weaknesses within the broader criminal justice system. For example, SA continues to experience severe forensic backlogs, particularly in DNA analysis and digital forensic processing. Reports indicate that the SAPS faces a DNA backlog exceeding 140,000 cases, largely due to increasing forensic demands and limited laboratory capacity.

Such constraints inevitably affect prosecutorial readiness, trial delays, and evidentiary reliability. In this environment, sustained conviction rates may indicate prosecutorial resilience and effective case selection rather than institutional complacency.

Moreover, contemporary prosecutorial performance cannot be divorced from the growing phenomenon of “Stalingrad litigation tactics”, particularly in corruption and State Capture-related prosecutions. Accused persons increasingly utilise extensive interlocutory applications, procedural challenges, and appeals to delay prosecutions indefinitely. In this regard, the recent order of the KwaZulu-Natal Division of the High Court in Pietermaritzburg for a matter to proceed on trial, notwithstanding ongoing “Stalingrad tactics”, marks a critical turn towards more effective case management.

The significance of conviction rates, therefore, lies not only in the outcome but also in the prosecution’s ability to withstand prolonged procedural obstruction while preserving evidentiary integrity and constitutional fairness.

Critics frequently argue that high conviction rates may reflect selective prosecution practices whereby prosecutors enrol only cases with overwhelming prospects of success. However, this criticism overlooks a fundamental ethical principle recognised both domestically and internationally: prosecutors are under a constitutional duty not to prosecute matters lacking sufficient evidence.

South African courts have repeatedly affirmed that prosecutorial discretion must be exercised rationally and in accordance with constitutional principles. In Democratic Alliance v Acting National Director of Public Prosecutions, the court confirmed that prosecutorial decisions must be informed by legality, rationality and evidentiary sufficiency. Similarly, in National Director of Public Prosecutions v Zuma, the judiciary recognised the centrality of prosecutorial discretion within the constitutional framework.

The ‘reasonable prospect of conviction’ standard

Thus, a high conviction rate may signify that prosecutors are properly applying the “reasonable prospect of conviction” standard rather than indiscriminately enrolling weak or speculative matters. In fact, indiscriminate prosecution would probably undermine fair trial rights, increase acquittal rates, exacerbate court backlogs and diminish public confidence in the administration of justice.

Nevertheless, conviction rates remain indispensable because they continue to measure the core constitutional function of prosecutors: the successful presentation of legally sustainable cases in court. Without convictions secured through fair judicial process, prosecutorial authority cannot meaningfully fulfil its constitutional mandate. The challenge, therefore, is not to abandon conviction rates as a measure of prosecutorial success, but rather to interpret them within the broader realities of SA’s evolving criminal justice environment and supplement them with additional indicators that capture institutional complexity, systemic constraints and broader justice outcomes.

The constitutional role of prosecutors further supports the legitimacy of conviction rates as a performance indicator. Section 179 of the Constitution entrusts the NPA with the authority to institute criminal proceedings on behalf of the state. Prosecutors neither investigate crimes independently nor determine guilt; that function rests with the judiciary. Their responsibility is to place before the court cases supported by sufficient admissible evidence capable of proving guilt beyond a reasonable doubt.

The principle that weak or speculative cases should not be prosecuted is also reflected internationally. The United Nations Guidelines on the Role of Prosecutors require prosecutors to perform their duties impartially and to refrain from pursuing prosecutions lacking an adequate evidentiary foundation. Comparable standards exist in jurisdictions such as the United Kingdom, Canada and Australia, all of which employ forms of conviction outcomes as indicators of prosecutorial effectiveness, while simultaneously recognising broader justice considerations.

Critics of conviction rates often fail to appreciate that high conviction rates may signify effective prosecutorial gatekeeping rather than statistical manipulation. Ethical prosecutors are expected to decline cases where evidence is insufficient, witnesses unreliable, or investigations incomplete.

Such decisions are not indicative of institutional failure, but rather compliance with constitutional obligations and fair trial standards. Were prosecutors to enrol every reported case indiscriminately in pursuit of throughput statistics, acquittal rates would inevitably increase, undermining judicial efficiency, fair trial rights and public confidence in the administration of justice.

The South African prosecutorial environment presents exceptional challenges. The NPA operates within a context characterised by high levels of violent crime, organised criminal syndicates, forensic backlogs, sophisticated corruption networks, and increasing reliance on so-called “Stalingrad tactics” designed to delay prosecutions indefinitely.

Prosecutorial complexity

High-profile corruption matters associated with State Capture have further intensified prosecutorial complexity, often involving transnational financial structures, digital evidence and vulnerable witnesses who require extensive protective measures.

Nevertheless, conviction rates do not function in isolation. A sophisticated prosecutorial performance framework requires complementary indicators that reflect the multifaceted nature of justice delivery. That is why the NPA also reports on measures relating to witness protection effectiveness, asset forfeiture outcomes and the successful prosecution of priority crimes such as corruption and organised crime.

The NPA’s Investigating Directorate Against Corruption employs a prosecutor-led investigative model, illustrating the importance of supplementary indicators such as case authorisations, preservation orders and asset recovery mechanisms in evaluating institutional effectiveness.

However, even within such expanded frameworks, conviction rates remain indispensable because they directly assess the prosecutor’s core constitutional function: securing lawful convictions through fair judicial process.

Ultimately, the appropriate conclusion is not that conviction rates are invalid or obsolete, but rather that they must be interpreted carefully and supplemented by broader justice indicators. Conviction rates continue to serve as a rational, constitutionally defensible and internationally recognised measure of prosecutorial performance.

Properly contextualised, they remain an essential indicator of prosecutorial competence, ethical discretion, evidentiary rigour, and institutional effectiveness within SA’s constitutional democracy. DM