The Formosa Case: A Step Forward on the Acceptance of Citizen-Collected Evidence in Environmental Litigation?

In June 2019, a landmark court decision (San Antonio Bay Estuarine Waterkeeper, et al. v. Formosa Plastics Corporation, et al., hereafter referred to as the Formosa ruling) was issued in Texas, where a judge found a petrochemical company liable for violating the United States Clean Water Act. The case—initiated by a civic group—was mostly built on citizen-collected evidence involving volunteer observations of plastic pellets, powder and flakes in the water over a considerable time span. The contamination could not be proven through existing data held by competent authorities because the company never filed any record of pollution (Formosa ruling, XI.A, p. 17).1 In contrast to the majority of environmental pollution cases to date, the monitoring and data collection for this case was conducted by local residents who gathered a wealth of evidence of plastic pollution in water. Through a traditional case law and text analysis of the Formosa ruling, complemented by the analysis of surrounding communications, we explore why and how citizen-collected evidence was admitted and influenced the judge’s ruling. Although the case has some unique features, we identify possible arguments and lessons learned for other citizen-run monitoring initiatives, to strengthen their voice within environmental litigation. We close by suggesting an avenue for future research—especially in the European context, where the discussion is still in its infancy.