The eff ect of group threat on voter mobilization has been tested using observational data across a number of di fferent geographies and units of analysis. Previous studies have yielded inconsistent findings. To date, no study of voter mobilization has directly manipulated group threat using a controlled experiment. I take advantage of the unique racial geography of Los Angeles County, California, which brings di fferent racial/ethnic groups into close, yet spatially separated, proximity. This geography allows for a randomized, controlled experiment to directly test the eff ects of stimulating racial threat on voter turnout. A test of 3,666 African American and Hispanic voters shows an average treatment e ffect of 2.3 percentage points. The e ect is 50% larger for African Americans than Hispanics. These results suggest that even low propensity voters are aware of the geographic proximity of other groups and can be motivated to participate by this awareness.
Also see discussion here about the ethics of the experiment.
