The resources of competition authorities are finite, meaning they cannot investigate all potential infringements of competition law, advocate against all impediments to competition, or research all areas of interest. To borrow from Confucius, if you chase two rabbits, you will catch neither. How competition authorities decide which cases to prioritise or prosecute is therefore important in ensuring limited resources have as much impact as possible. With recent data suggesting an overall decline in number of competition enforcement cases (OECD, 2025[1]), competition authorities will likely come under increasing pressure to demonstrate their efficacy. It is therefore an opportune time to consider how best they can prioritise their cases and when, and when not, to exercise prosecutorial discretion.1
Most competition authorities identify strategies to achieve their aims. As part of this they often set high-level priorities by identifying activities or sectors to concentrate on. They must also decide how to organise their resources and staff. This paper will focus on case prioritisation rather than high-level priorities or other strategies, narrowing in on the choice of individual cases and how these decisions are made. Nonetheless, despite this focus, the paper will need to consider how other levels of prioritisation might influence case prioritisation. For example, a decision to commence a specific cartel investigation may be influenced by whether or not tackling cartels has been identified as a high-level priority by the authority.
Whether a competition regime is administrative or prosecutorial may affect how case prioritisation decisions are made. Nonetheless, there are many similarities between case prioritisation and prosecutorial discretion. For example, both must decide where to devote resources in order to maximise impact, even if the processes and procedures may vary. For simplicity, the paper will use case prioritisation to also describe prosecutorial discretion, but will discuss when differences may emerge between the two.
Case prioritisation, to be effective, needs to include a holistic assessment of competing demands and opportunity costs.2 As such, while much of the discussion in this paper will focus on traditional enforcement areas, such as abuse of dominance and cartels, the paper will also consider a broad definition of “case”. In particular, the discussion will also cover prioritisation decisions in relation to advocacy, mergers, market studies, as well as other forms of research, such as ex-post assessments. This will allow the paper to consider how approaches may differ across tools. Similarly, as it relates to decisions on cases and resources, case prioritisation could also relate to the detailed strategies that authorities pursue on each case. This paper focusses on decisions on which cases to pursue and continue, while noting that how cases are pursued will also have a bearing on overall prioritisation.
To have the freedom to prioritise across cases, competition authorities require a degree of discretion, although there will be flexibility to adjust resources. How much discretion competition authorities should have, as bodies typically independent from government, has been subject to some debate, and priority setting by authorities depends on their legal and institutional context (Brook and Cseres, 2021[2]).
A range of factors are relevant to competition authorities as they consider case prioritisation decisions. Considering these factors and the theoretical underpinnings of decisions can provide a useful framework to evaluate existing practice. At the same time, reality is unlikely to be as simple as a theoretical assessment might suggest. Prioritisation is important, but authorities will devote most of their resources to delivering cases, as perfectly prioritising would be of little value without an end product. Authorities must also deal with the political reality of being a public facing body that cannot perfectly predict the future. As such, this paper aims to consider both the theoretical and practical aspects of case prioritisation.
The OECD Competition Committee has not held a dedicated discussion on case prioritisation before. However, the OECD has conducted several related pieces of work. For example, it has held workshops or discussions considering elements of case prioritisation, such as how to select sectors for market studies (OECD, 2017[3]) or incorporating gender as a prioritisation principle (Kovacic, 2021[4]). A survey conducted in 2012 of OECD delegates evaluating competition enforcement and advocacy activities also included a series of questions relating to high-level priority setting (OECD, 2013[5]). More generally, the Committee’s substantial catalogue of best practice competition policy roundtables have touched on many topics of value when considering case prioritisation, such as those that relate to measuring market competition (OECD, 2021[6]), assessing the impact of authorities activities3 and the many that consider competition in sectors and effective use of competition tools.4
Other international organisations have worked on case prioritisation: the International Competition Network (ICN) published a report on Agencies’ Case Prioritisation and Initiation (ICN, 2021[7]), as well as a chapter on Strategic Planning and Prioritisation in its Agency Effectiveness Manual (ICN, 2010[8]); the United Nations Conference on Trade and Development (UNCTAD) held a roundtable discussion on priority setting and resource allocation as a tool for agency effectiveness in July 2013, including a secretariat background note (UNCTAD, 2013[9]); and the European Competition Network (ECN) also published a Recommendation on the Power for ECN Competition Authorities to Set Priorities (ECN, 2021[10]).
To support this paper, the OECD conducted a short survey (the OECD Survey) of competition authorities to better understand several aspects of how they make case prioritisation decisions. The OECD Survey received 30 responses, and its results are referred to throughout the paper where relevant. A detailed summary of the findings are provided in the Annex.
The structure of this paper is as follows. Section 2 considers what we mean by case prioritisation and how it fits alongside broader high-level priority setting. Section 3 discusses the role and limits for prioritisation by competition authorities, including the constraints that should apply and the potential policy reasons for more, or less, discretion. Section 4 focusses on the factors relevant to case prioritisation decisions, as well as considerations for different tools and actions, and Section 5 considers more practical aspects, such as case prioritisation processes and the gathering of relevant information. The final section concludes and discusses potential future work.