Very little is known about the complaint investigation process in the Office for Civil Rights, despite its scope and reach. We examine key parameters (number and types of complaints received, types of resolutions, average time of resolution) of civil rights complaints nationwide over a 20-year period (1999-2019). We find that 10%-40% of all districts receive at least one discrimination-related complaint each year. We also find that complaints are filed at significantly higher rates in large districts and districts with a high percentage of Black students, even after controlling for other structural factors, such as average socioeconomic status and locale.