# Targeted digital voter suppression efforts likely decrease voter turnout

## TL;DR

This study shows that targeted digital voter suppression ads, especially in minority areas, may reduce voter turnout in elections.

## Contribution

The study provides the first empirical evidence linking digital voter suppression ads to decreased voter turnout.

## Key findings

- Digital voter suppression disproportionately targeted non-Whites in minority counties of battleground states.
- Exposure to voter suppression ads was associated with lower voter turnout, particularly among non-Whites in minority counties.

## Abstract

Although governments have repeatedly flagged digital voter suppression in recent elections, such reports have remained anecdotal. Using a sample that mirrors the US voting-age population, this study provides first systematic empirical documentation of undisclosed digital voter suppression, including foreign election interference, based on the case of the 2016 US Presidential Election. By tracking each user’s digital ad exposure, demographic profiles, and verified voting records, this study reveals that digital voter suppression disproportionally targeted non-Whites in racial minority counties of battleground states. Individuals exposed to digital voter suppression ads were less likely to vote. The findings offer real-world evidence that targeted digital voter suppression may decrease voter turnout, raising serious concerns about election integrity in data-driven, microtargeted information environments.

In light of continued foreign interference in the US presidential elections, where undisclosed digital voter suppression advertising has been deployed, this study addresses the questions of who is exposed to these ads and whether and how such exposure influences voter turnout. Using a sample that resembles the US voting-age population, the study directly measures each individual’s ad exposure through a user-level real-time ad tracking tool, which is merged with the same individual’s survey responses to identify voter suppression content and its targeting patterns. By further matching individual-level exposure to voter suppression ads with the same individual’s verified voter turnout records, the study estimates the effects of voter suppression on actual turnout. The study findings from the 2016 US Presidential Election reveal clear geo-racial targeting patterns in voter suppression: non-Whites residing in the racial minority counties of battleground states were exposed to substantially more voter suppression ads than their counterparts. Moreover, exposure to voter suppression ads was associated with decreases in voter turnout at the population level, albeit small. The sharpest declines were observed among non-Whites residing in minority counties of battleground states, suggesting that the intensified turnout suppression among the targeted segments of the electorate may have played a role in shaping turnout.