5 Questions is a periodic feature produced by Cornerstone Research, which asks our affiliated experts and senior professionals to answer five questions related to their work.
We interview Joanna Tsai, cohead of Cornerstone Research’s merger investigations practice, to gain her insights on delivering effective testimony in high-stakes cases, as well as the broader changes shaping competition economics today.
Dr. Tsai discusses the essential skills needed for presenting successful data analysis, the greatest challenges competition economists currently face, and the importance of objectivity in the field of antitrust.
What are the key skills required to successfully deliver testimony in high-stakes, high-value cases as an economist?
In my view, delivering successful testimony and agency presentations requires the ability to identify and analyze the key issues in a given matter, and explain—clearly and thoughtfully—why those issues are important. It is also critical to be able to ground economic analyses in high-quality data and, when appropriate, to account for gaps or shortfalls in the data. No dataset is perfect, and ignoring potential imperfections in the data, rather than addressing them head on, diminishes an economist’s credibility.
What is the greatest challenge currently faced by competition economists and how can it be effectively tackled?
I believe that one of the great challenges that competition economists face today is how best to connect with judges and decision-makers at the agencies and to explain the economics relevant to the case at hand. Some decision-makers have noted in the past that sometimes economists would present conclusions that were valid only if you looked to the third (or sixth!) decimal place or imposed a particular assumption. It is impossible to overstate the importance of conducting sensitivity checks for economic analyses. Understanding how an economic model might or might not be sensitive to certain assumptions is essential to productive conversations with the agencies and in the courts. Explaining how the economics and the results of the analyses are relevant and robust is also critically important, especially when presenting to generalist judges.
No dataset is perfect, and ignoring potential imperfections in the data, rather than addressing them head on, diminishes an economist’s credibility
How has antitrust as a practice area changed since you started your career? Has it changed for women—and if so, how?
Antitrust, including merger reviews and analysis, has evolved significantly since I started practicing. The first version of the merger guidelines I worked with dated from 1997. Since then, I have seen the issuance and implementation of the 2010 guidelines and, of course, the 2023 draft merger guidelines. The agencies are continually sharpening analyses of various issues related to mergers and striving to accommodate changes in our world. Many thoughtful comments were submitted to the Federal Trade Commission and the Department of Justice in the latest review of the draft merger guidelines, and I look forward to the new perspectives that will arise in this latest chapter of engagement with the agencies.
With respect to how antitrust has changed for women, I am delighted and excited to see many qualified women entering the field. This enriches the practice area, bringing fresh experience and perspectives to shape the future of antitrust law and policy.
A balanced approach is necessary, one that combines the benefits of greater attention and resources with the need for objective, evidence-based analysis and decision-making.
Does the increasing politicization of antitrust enforcement present an opportunity or is it cause for concern?
As public interest in antitrust issues expands, I see both opportunities and challenges. On one hand, such interest can lead to increased thinking, resources, and research in the field, which benefits competition policy and the economy. In a nutshell: More focus on antitrust issues can lead to the development of more effective analytical frameworks.
On the other hand, politicization can lead to inconsistent, unpredictable enforcement, potentially undermining the rule of law and the integrity of the competition process. A balanced approach is necessary, one that combines the benefits of greater attention and resources with the need for objective, evidence-based analysis and decision-making.
Do you expect to see more divergence or harmonization between antitrust enforcers in the coming years?
While agencies across the world continue to coordinate, each jurisdiction’s unique competitive landscape will likely lead to varying outcomes and decision-making approaches.
Antitrust enforcers play a crucial role in promoting competition and protecting consumers by reviewing mergers, investigating anticompetitive practices, and enforcing laws to prevent exercise of market power. A collaborative approach between and among enforcers is essential, allowing them to share best practices, coordinate on complex matters, and support consistent application of competition policy across borders.
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