We examine changes in the nature and rate of complaints filed with the federal Equal Employment Opportunity Commission (EEOC) in the past 35 years. The EEOC's role has shifted over this period from ensuring job access for racial minorities to providing diverse protections for a much broader class of incumbent workers. We first describe trends in discrimination complaints, most notably the shift from racial discrimination to other bases of discrimination, and develop a conceptual model of choice among socially structured alternatives to account for them. We then test the model with a time series analysis of changes in the complaint rate among different worker groups to evaluate the relative importance of legal, political, and socioeconomic determinants of civil rights complaints. Net of changes in the political climate, benefit compensation, inequality, and education levels, we find that legal changes and group-specific unemployment rates are the strongest and most consistent determinants of the rate of race, sex, and total discrimination complaints. Our results suggest that people will bear the costs of filing a complaint when legal options are relatively attractive and when employment options on the external labor market are unattractive.