The main purpose of this paper is to illustrate the application of causal inference method to administrative data and the challenges of such application. We illustrate by applying Bayesian networks method to 311 data from Miami-Dade County, Florida (USA). The 311 centers provide non-emergency services to residents. The 311 data are large and granular. We aim to explore the equity issues and biases that might exist in this particular type of service requests. As a case study, the relationship between population characteristics (independent variables) and request volume and completion time (dependent variables) is examined to identify the disparities, if any, from the observational data. The empirical analysis shows that there are no biases in services provided to any specific demographic, socioeconomic, or geographical groups. However, the administrative data do have various challenges for inferring causality due to missing or impure data, inadequacy, and latent confounders. The precautions of applying causal techniques to analyzing administrative data like 311 are discussed.
