But Can You Use It? Design Recommendations for Differentially Private Interactive Systems
Liudas Panavas, Joshua Snoke, Erika Tyagi, Claire McKay Bowen, Aaron R. Williams
TL;DR
The paper tackles the practical deployment of differential privacy in interactive query systems (validation servers) for federal statistics by reconciling privacy, utility, and usability. It proposes a triad design framework—privacy assurance, statistical utility, and system usability—and translates it into concrete system recommendations (synthetic data for exploration, removing DP parameter inputs, per-project privacy allocation, light human review, and publication-ready output documentation) along with a high-level infrastructure plan leveraging open-source DP libraries. By foregrounding usability and user testing, the authors argue for a paradigm shift that blends DP with practical statistical practice to better inform public policy. The work also outlines a program of user research and infrastructure development needed to validate and operationalize this approach, and discusses potential trade-offs and future directions.
Abstract
Accessing data collected by federal statistical agencies is essential for public policy research and improving evidence-based decision making, such as evaluating the effectiveness of social programs, understanding demographic shifts, or addressing public health challenges. Differentially private interactive systems, or validation servers, can form a crucial part of the data-sharing infrastructure. They may allow researchers to query targeted statistics, providing flexible, efficient access to specific insights, reducing the need for broad data releases and supporting timely, focused research. However, they have not yet been practically implemented. While substantial theoretical work has been conducted on the privacy and accuracy guarantees of differentially private mechanisms, prior efforts have not considered usability as an explicit goal of interactive systems. This work outlines and considers the barriers to developing differentially private interactive systems for informing public policy and offers an alternative way forward. We propose balancing three design considerations: privacy assurance, statistical utility, and system usability, we develop recommendations for making differentially private interactive systems work in practice, we present an example architecture based on these recommendations, and we provide an outline of how to conduct the necessary user-testing. Our work seeks to move the practical development of differentially private interactive systems forward to better aid public policy making and spark future research.
